1270 lines
		
	
	
		
			35 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1270 lines
		
	
	
		
			35 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-only
 | |
| // Copyright (C) 2014 Broadcom Corporation
 | |
| 
 | |
| #include <linux/delay.h>
 | |
| #include <linux/i2c.h>
 | |
| #include <linux/interrupt.h>
 | |
| #include <linux/io.h>
 | |
| #include <linux/kernel.h>
 | |
| #include <linux/module.h>
 | |
| #include <linux/of_device.h>
 | |
| #include <linux/platform_device.h>
 | |
| #include <linux/slab.h>
 | |
| 
 | |
| #define IDM_CTRL_DIRECT_OFFSET       0x00
 | |
| #define CFG_OFFSET                   0x00
 | |
| #define CFG_RESET_SHIFT              31
 | |
| #define CFG_EN_SHIFT                 30
 | |
| #define CFG_SLAVE_ADDR_0_SHIFT       28
 | |
| #define CFG_M_RETRY_CNT_SHIFT        16
 | |
| #define CFG_M_RETRY_CNT_MASK         0x0f
 | |
| 
 | |
| #define TIM_CFG_OFFSET               0x04
 | |
| #define TIM_CFG_MODE_400_SHIFT       31
 | |
| #define TIM_RAND_SLAVE_STRETCH_SHIFT      24
 | |
| #define TIM_RAND_SLAVE_STRETCH_MASK       0x7f
 | |
| #define TIM_PERIODIC_SLAVE_STRETCH_SHIFT  16
 | |
| #define TIM_PERIODIC_SLAVE_STRETCH_MASK   0x7f
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| 
 | |
| #define S_CFG_SMBUS_ADDR_OFFSET           0x08
 | |
| #define S_CFG_EN_NIC_SMB_ADDR3_SHIFT      31
 | |
| #define S_CFG_NIC_SMB_ADDR3_SHIFT         24
 | |
| #define S_CFG_NIC_SMB_ADDR3_MASK          0x7f
 | |
| #define S_CFG_EN_NIC_SMB_ADDR2_SHIFT      23
 | |
| #define S_CFG_NIC_SMB_ADDR2_SHIFT         16
 | |
| #define S_CFG_NIC_SMB_ADDR2_MASK          0x7f
 | |
| #define S_CFG_EN_NIC_SMB_ADDR1_SHIFT      15
 | |
| #define S_CFG_NIC_SMB_ADDR1_SHIFT         8
 | |
| #define S_CFG_NIC_SMB_ADDR1_MASK          0x7f
 | |
| #define S_CFG_EN_NIC_SMB_ADDR0_SHIFT      7
 | |
| #define S_CFG_NIC_SMB_ADDR0_SHIFT         0
 | |
| #define S_CFG_NIC_SMB_ADDR0_MASK          0x7f
 | |
| 
 | |
| #define M_FIFO_CTRL_OFFSET           0x0c
 | |
| #define M_FIFO_RX_FLUSH_SHIFT        31
 | |
| #define M_FIFO_TX_FLUSH_SHIFT        30
 | |
| #define M_FIFO_RX_CNT_SHIFT          16
 | |
| #define M_FIFO_RX_CNT_MASK           0x7f
 | |
| #define M_FIFO_RX_THLD_SHIFT         8
 | |
| #define M_FIFO_RX_THLD_MASK          0x3f
 | |
| 
 | |
| #define S_FIFO_CTRL_OFFSET           0x10
 | |
| #define S_FIFO_RX_FLUSH_SHIFT        31
 | |
| #define S_FIFO_TX_FLUSH_SHIFT        30
 | |
| #define S_FIFO_RX_CNT_SHIFT          16
 | |
| #define S_FIFO_RX_CNT_MASK           0x7f
 | |
| #define S_FIFO_RX_THLD_SHIFT         8
 | |
| #define S_FIFO_RX_THLD_MASK          0x3f
 | |
| 
 | |
| #define M_CMD_OFFSET                 0x30
 | |
| #define M_CMD_START_BUSY_SHIFT       31
 | |
| #define M_CMD_STATUS_SHIFT           25
 | |
| #define M_CMD_STATUS_MASK            0x07
 | |
| #define M_CMD_STATUS_SUCCESS         0x0
 | |
| #define M_CMD_STATUS_LOST_ARB        0x1
 | |
| #define M_CMD_STATUS_NACK_ADDR       0x2
 | |
| #define M_CMD_STATUS_NACK_DATA       0x3
 | |
| #define M_CMD_STATUS_TIMEOUT         0x4
 | |
| #define M_CMD_STATUS_FIFO_UNDERRUN   0x5
 | |
| #define M_CMD_STATUS_RX_FIFO_FULL    0x6
 | |
| #define M_CMD_PROTOCOL_SHIFT         9
 | |
| #define M_CMD_PROTOCOL_MASK          0xf
 | |
| #define M_CMD_PROTOCOL_QUICK         0x0
 | |
| #define M_CMD_PROTOCOL_BLK_WR        0x7
 | |
| #define M_CMD_PROTOCOL_BLK_RD        0x8
 | |
| #define M_CMD_PROTOCOL_PROCESS       0xa
 | |
| #define M_CMD_PEC_SHIFT              8
 | |
| #define M_CMD_RD_CNT_SHIFT           0
 | |
| #define M_CMD_RD_CNT_MASK            0xff
 | |
| 
 | |
| #define S_CMD_OFFSET                 0x34
 | |
| #define S_CMD_START_BUSY_SHIFT       31
 | |
| #define S_CMD_STATUS_SHIFT           23
 | |
| #define S_CMD_STATUS_MASK            0x07
 | |
| #define S_CMD_STATUS_SUCCESS         0x0
 | |
| #define S_CMD_STATUS_TIMEOUT         0x5
 | |
| #define S_CMD_STATUS_MASTER_ABORT    0x7
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| 
 | |
| #define IE_OFFSET                    0x38
 | |
| #define IE_M_RX_FIFO_FULL_SHIFT      31
 | |
| #define IE_M_RX_THLD_SHIFT           30
 | |
| #define IE_M_START_BUSY_SHIFT        28
 | |
| #define IE_M_TX_UNDERRUN_SHIFT       27
 | |
| #define IE_S_RX_FIFO_FULL_SHIFT      26
 | |
| #define IE_S_RX_THLD_SHIFT           25
 | |
| #define IE_S_RX_EVENT_SHIFT          24
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| #define IE_S_START_BUSY_SHIFT        23
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| #define IE_S_TX_UNDERRUN_SHIFT       22
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| #define IE_S_RD_EVENT_SHIFT          21
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| 
 | |
| #define IS_OFFSET                    0x3c
 | |
| #define IS_M_RX_FIFO_FULL_SHIFT      31
 | |
| #define IS_M_RX_THLD_SHIFT           30
 | |
| #define IS_M_START_BUSY_SHIFT        28
 | |
| #define IS_M_TX_UNDERRUN_SHIFT       27
 | |
| #define IS_S_RX_FIFO_FULL_SHIFT      26
 | |
| #define IS_S_RX_THLD_SHIFT           25
 | |
| #define IS_S_RX_EVENT_SHIFT          24
 | |
| #define IS_S_START_BUSY_SHIFT        23
 | |
| #define IS_S_TX_UNDERRUN_SHIFT       22
 | |
| #define IS_S_RD_EVENT_SHIFT          21
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| 
 | |
| #define M_TX_OFFSET                  0x40
 | |
| #define M_TX_WR_STATUS_SHIFT         31
 | |
| #define M_TX_DATA_SHIFT              0
 | |
| #define M_TX_DATA_MASK               0xff
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| 
 | |
| #define M_RX_OFFSET                  0x44
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| #define M_RX_STATUS_SHIFT            30
 | |
| #define M_RX_STATUS_MASK             0x03
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| #define M_RX_PEC_ERR_SHIFT           29
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| #define M_RX_DATA_SHIFT              0
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| #define M_RX_DATA_MASK               0xff
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| 
 | |
| #define S_TX_OFFSET                  0x48
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| #define S_TX_WR_STATUS_SHIFT         31
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| #define S_TX_DATA_SHIFT              0
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| #define S_TX_DATA_MASK               0xff
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| 
 | |
| #define S_RX_OFFSET                  0x4c
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| #define S_RX_STATUS_SHIFT            30
 | |
| #define S_RX_STATUS_MASK             0x03
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| #define S_RX_PEC_ERR_SHIFT           29
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| #define S_RX_DATA_SHIFT              0
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| #define S_RX_DATA_MASK               0xff
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| 
 | |
| #define I2C_TIMEOUT_MSEC             50000
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| #define M_TX_RX_FIFO_SIZE            64
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| #define M_RX_FIFO_MAX_THLD_VALUE     (M_TX_RX_FIFO_SIZE - 1)
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| 
 | |
| #define M_RX_MAX_READ_LEN            255
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| #define M_RX_FIFO_THLD_VALUE         50
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| 
 | |
| #define IE_M_ALL_INTERRUPT_SHIFT     27
 | |
| #define IE_M_ALL_INTERRUPT_MASK      0x1e
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| 
 | |
| #define SLAVE_READ_WRITE_BIT_MASK    0x1
 | |
| #define SLAVE_READ_WRITE_BIT_SHIFT   0x1
 | |
| #define SLAVE_MAX_SIZE_TRANSACTION   64
 | |
| #define SLAVE_CLOCK_STRETCH_TIME     25
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| 
 | |
| #define IE_S_ALL_INTERRUPT_SHIFT     21
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| #define IE_S_ALL_INTERRUPT_MASK      0x3f
 | |
| /*
 | |
|  * It takes ~18us to reading 10bytes of data, hence to keep tasklet
 | |
|  * running for less time, max slave read per tasklet is set to 10 bytes.
 | |
|  */
 | |
| #define MAX_SLAVE_RX_PER_INT         10
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| 
 | |
| enum i2c_slave_read_status {
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| 	I2C_SLAVE_RX_FIFO_EMPTY = 0,
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| 	I2C_SLAVE_RX_START,
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| 	I2C_SLAVE_RX_DATA,
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| 	I2C_SLAVE_RX_END,
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| };
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| 
 | |
| enum bus_speed_index {
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| 	I2C_SPD_100K = 0,
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| 	I2C_SPD_400K,
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| };
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| 
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| enum bcm_iproc_i2c_type {
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| 	IPROC_I2C,
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| 	IPROC_I2C_NIC
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| };
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| 
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| struct bcm_iproc_i2c_dev {
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| 	struct device *device;
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| 	enum bcm_iproc_i2c_type type;
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| 	int irq;
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| 
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| 	void __iomem *base;
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| 	void __iomem *idm_base;
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| 
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| 	u32 ape_addr_mask;
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| 
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| 	/* lock for indirect access through IDM */
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| 	spinlock_t idm_lock;
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| 
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| 	struct i2c_adapter adapter;
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| 	unsigned int bus_speed;
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| 
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| 	struct completion done;
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| 	int xfer_is_done;
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| 
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| 	struct i2c_msg *msg;
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| 
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| 	struct i2c_client *slave;
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| 
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| 	/* bytes that have been transferred */
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| 	unsigned int tx_bytes;
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| 	/* bytes that have been read */
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| 	unsigned int rx_bytes;
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| 	unsigned int thld_bytes;
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| 
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| 	bool slave_rx_only;
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| 	bool rx_start_rcvd;
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| 	bool slave_read_complete;
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| 	u32 tx_underrun;
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| 	u32 slave_int_mask;
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| 	struct tasklet_struct slave_rx_tasklet;
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| };
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| 
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| /* tasklet to process slave rx data */
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| static void slave_rx_tasklet_fn(unsigned long);
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| 
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| /*
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|  * Can be expanded in the future if more interrupt status bits are utilized
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|  */
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| #define ISR_MASK (BIT(IS_M_START_BUSY_SHIFT) | BIT(IS_M_TX_UNDERRUN_SHIFT)\
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| 		| BIT(IS_M_RX_THLD_SHIFT))
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| 
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| #define ISR_MASK_SLAVE (BIT(IS_S_START_BUSY_SHIFT)\
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| 		| BIT(IS_S_RX_EVENT_SHIFT) | BIT(IS_S_RD_EVENT_SHIFT)\
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| 		| BIT(IS_S_TX_UNDERRUN_SHIFT) | BIT(IS_S_RX_FIFO_FULL_SHIFT)\
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| 		| BIT(IS_S_RX_THLD_SHIFT))
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| 
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| static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave);
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| static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave);
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| static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,
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| 					 bool enable);
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| 
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| static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
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| 				   u32 offset)
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| {
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| 	u32 val;
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| 
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| 	if (iproc_i2c->idm_base) {
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| 		spin_lock(&iproc_i2c->idm_lock);
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| 		writel(iproc_i2c->ape_addr_mask,
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| 		       iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
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| 		val = readl(iproc_i2c->base + offset);
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| 		spin_unlock(&iproc_i2c->idm_lock);
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| 	} else {
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| 		val = readl(iproc_i2c->base + offset);
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| 	}
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| 
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| 	return val;
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| }
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| 
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| static inline void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
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| 				    u32 offset, u32 val)
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| {
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| 	if (iproc_i2c->idm_base) {
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| 		spin_lock(&iproc_i2c->idm_lock);
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| 		writel(iproc_i2c->ape_addr_mask,
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| 		       iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
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| 		writel(val, iproc_i2c->base + offset);
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| 		spin_unlock(&iproc_i2c->idm_lock);
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| 	} else {
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| 		writel(val, iproc_i2c->base + offset);
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| 	}
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| }
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| 
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| static void bcm_iproc_i2c_slave_init(
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| 	struct bcm_iproc_i2c_dev *iproc_i2c, bool need_reset)
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| {
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| 	u32 val;
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| 
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| 	iproc_i2c->tx_underrun = 0;
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| 	if (need_reset) {
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| 		/* put controller in reset */
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| 		val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
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| 		val |= BIT(CFG_RESET_SHIFT);
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| 		iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
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| 
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| 		/* wait 100 usec per spec */
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| 		udelay(100);
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| 
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| 		/* bring controller out of reset */
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| 		val &= ~(BIT(CFG_RESET_SHIFT));
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| 		iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
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| 	}
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| 
 | |
| 	/* flush TX/RX FIFOs */
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| 	val = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT));
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| 	iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val);
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| 
 | |
| 	/* Maximum slave stretch time */
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| 	val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
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| 	val &= ~(TIM_RAND_SLAVE_STRETCH_MASK << TIM_RAND_SLAVE_STRETCH_SHIFT);
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| 	val |= (SLAVE_CLOCK_STRETCH_TIME << TIM_RAND_SLAVE_STRETCH_SHIFT);
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| 	iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
 | |
| 
 | |
| 	/* Configure the slave address */
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| 	val = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET);
 | |
| 	val |= BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT);
 | |
| 	val &= ~(S_CFG_NIC_SMB_ADDR3_MASK << S_CFG_NIC_SMB_ADDR3_SHIFT);
 | |
| 	val |= (iproc_i2c->slave->addr << S_CFG_NIC_SMB_ADDR3_SHIFT);
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| 	iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, val);
 | |
| 
 | |
| 	/* clear all pending slave interrupts */
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| 	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE);
 | |
| 
 | |
| 	/* Enable interrupt register to indicate a valid byte in receive fifo */
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| 	val = BIT(IE_S_RX_EVENT_SHIFT);
 | |
| 	/* Enable interrupt register to indicate Slave Rx FIFO Full */
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| 	val |= BIT(IE_S_RX_FIFO_FULL_SHIFT);
 | |
| 	/* Enable interrupt register to indicate a Master read transaction */
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| 	val |= BIT(IE_S_RD_EVENT_SHIFT);
 | |
| 	/* Enable interrupt register for the Slave BUSY command */
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| 	val |= BIT(IE_S_START_BUSY_SHIFT);
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| 	iproc_i2c->slave_int_mask = val;
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| 	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
 | |
| }
 | |
| 
 | |
| static void bcm_iproc_i2c_check_slave_status(
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| 	struct bcm_iproc_i2c_dev *iproc_i2c)
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| {
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| 	u32 val;
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| 
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| 	val = iproc_i2c_rd_reg(iproc_i2c, S_CMD_OFFSET);
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| 	/* status is valid only when START_BUSY is cleared after it was set */
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| 	if (val & BIT(S_CMD_START_BUSY_SHIFT))
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| 		return;
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| 
 | |
| 	val = (val >> S_CMD_STATUS_SHIFT) & S_CMD_STATUS_MASK;
 | |
| 	if (val == S_CMD_STATUS_TIMEOUT || val == S_CMD_STATUS_MASTER_ABORT) {
 | |
| 		dev_err(iproc_i2c->device, (val == S_CMD_STATUS_TIMEOUT) ?
 | |
| 			"slave random stretch time timeout\n" :
 | |
| 			"Master aborted read transaction\n");
 | |
| 		/* re-initialize i2c for recovery */
 | |
| 		bcm_iproc_i2c_enable_disable(iproc_i2c, false);
 | |
| 		bcm_iproc_i2c_slave_init(iproc_i2c, true);
 | |
| 		bcm_iproc_i2c_enable_disable(iproc_i2c, true);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void bcm_iproc_i2c_slave_read(struct bcm_iproc_i2c_dev *iproc_i2c)
 | |
| {
 | |
| 	u8 rx_data, rx_status;
 | |
| 	u32 rx_bytes = 0;
 | |
| 	u32 val;
 | |
| 
 | |
| 	while (rx_bytes < MAX_SLAVE_RX_PER_INT) {
 | |
| 		val = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET);
 | |
| 		rx_status = (val >> S_RX_STATUS_SHIFT) & S_RX_STATUS_MASK;
 | |
| 		rx_data = ((val >> S_RX_DATA_SHIFT) & S_RX_DATA_MASK);
 | |
| 
 | |
| 		if (rx_status == I2C_SLAVE_RX_START) {
 | |
| 			/* Start of SMBUS Master write */
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| 			i2c_slave_event(iproc_i2c->slave,
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| 					I2C_SLAVE_WRITE_REQUESTED, &rx_data);
 | |
| 			iproc_i2c->rx_start_rcvd = true;
 | |
| 			iproc_i2c->slave_read_complete = false;
 | |
| 		} else if (rx_status == I2C_SLAVE_RX_DATA &&
 | |
| 			   iproc_i2c->rx_start_rcvd) {
 | |
| 			/* Middle of SMBUS Master write */
 | |
| 			i2c_slave_event(iproc_i2c->slave,
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| 					I2C_SLAVE_WRITE_RECEIVED, &rx_data);
 | |
| 		} else if (rx_status == I2C_SLAVE_RX_END &&
 | |
| 			   iproc_i2c->rx_start_rcvd) {
 | |
| 			/* End of SMBUS Master write */
 | |
| 			if (iproc_i2c->slave_rx_only)
 | |
| 				i2c_slave_event(iproc_i2c->slave,
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| 						I2C_SLAVE_WRITE_RECEIVED,
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| 						&rx_data);
 | |
| 
 | |
| 			i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP,
 | |
| 					&rx_data);
 | |
| 		} else if (rx_status == I2C_SLAVE_RX_FIFO_EMPTY) {
 | |
| 			iproc_i2c->rx_start_rcvd = false;
 | |
| 			iproc_i2c->slave_read_complete = true;
 | |
| 			break;
 | |
| 		}
 | |
| 
 | |
| 		rx_bytes++;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void slave_rx_tasklet_fn(unsigned long data)
 | |
| {
 | |
| 	struct bcm_iproc_i2c_dev *iproc_i2c = (struct bcm_iproc_i2c_dev *)data;
 | |
| 	u32 int_clr;
 | |
| 
 | |
| 	bcm_iproc_i2c_slave_read(iproc_i2c);
 | |
| 
 | |
| 	/* clear pending IS_S_RX_EVENT_SHIFT interrupt */
 | |
| 	int_clr = BIT(IS_S_RX_EVENT_SHIFT);
 | |
| 
 | |
| 	if (!iproc_i2c->slave_rx_only && iproc_i2c->slave_read_complete) {
 | |
| 		/*
 | |
| 		 * In case of single byte master-read request,
 | |
| 		 * IS_S_TX_UNDERRUN_SHIFT event is generated before
 | |
| 		 * IS_S_START_BUSY_SHIFT event. Hence start slave data send
 | |
| 		 * from first IS_S_TX_UNDERRUN_SHIFT event.
 | |
| 		 *
 | |
| 		 * This means don't send any data from slave when
 | |
| 		 * IS_S_RD_EVENT_SHIFT event is generated else it will increment
 | |
| 		 * eeprom or other backend slave driver read pointer twice.
 | |
| 		 */
 | |
| 		iproc_i2c->tx_underrun = 0;
 | |
| 		iproc_i2c->slave_int_mask |= BIT(IE_S_TX_UNDERRUN_SHIFT);
 | |
| 
 | |
| 		/* clear IS_S_RD_EVENT_SHIFT interrupt */
 | |
| 		int_clr |= BIT(IS_S_RD_EVENT_SHIFT);
 | |
| 	}
 | |
| 
 | |
| 	/* clear slave interrupt */
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, int_clr);
 | |
| 	/* enable slave interrupts */
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, iproc_i2c->slave_int_mask);
 | |
| }
 | |
| 
 | |
| static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c,
 | |
| 				    u32 status)
 | |
| {
 | |
| 	u32 val;
 | |
| 	u8 value;
 | |
| 
 | |
| 	/*
 | |
| 	 * Slave events in case of master-write, master-write-read and,
 | |
| 	 * master-read
 | |
| 	 *
 | |
| 	 * Master-write     : only IS_S_RX_EVENT_SHIFT event
 | |
| 	 * Master-write-read: both IS_S_RX_EVENT_SHIFT and IS_S_RD_EVENT_SHIFT
 | |
| 	 *                    events
 | |
| 	 * Master-read      : both IS_S_RX_EVENT_SHIFT and IS_S_RD_EVENT_SHIFT
 | |
| 	 *                    events or only IS_S_RD_EVENT_SHIFT
 | |
| 	 *
 | |
| 	 * iproc has a slave rx fifo size of 64 bytes. Rx fifo full interrupt
 | |
| 	 * (IS_S_RX_FIFO_FULL_SHIFT) will be generated when RX fifo becomes
 | |
| 	 * full. This can happen if Master issues write requests of more than
 | |
| 	 * 64 bytes.
 | |
| 	 */
 | |
| 	if (status & BIT(IS_S_RX_EVENT_SHIFT) ||
 | |
| 	    status & BIT(IS_S_RD_EVENT_SHIFT) ||
 | |
| 	    status & BIT(IS_S_RX_FIFO_FULL_SHIFT)) {
 | |
| 		/* disable slave interrupts */
 | |
| 		val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
 | |
| 		val &= ~iproc_i2c->slave_int_mask;
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
 | |
| 
 | |
| 		if (status & BIT(IS_S_RD_EVENT_SHIFT))
 | |
| 			/* Master-write-read request */
 | |
| 			iproc_i2c->slave_rx_only = false;
 | |
| 		else
 | |
| 			/* Master-write request only */
 | |
| 			iproc_i2c->slave_rx_only = true;
 | |
| 
 | |
| 		/* schedule tasklet to read data later */
 | |
| 		tasklet_schedule(&iproc_i2c->slave_rx_tasklet);
 | |
| 
 | |
| 		/*
 | |
| 		 * clear only IS_S_RX_EVENT_SHIFT and
 | |
| 		 * IS_S_RX_FIFO_FULL_SHIFT interrupt.
 | |
| 		 */
 | |
| 		val = BIT(IS_S_RX_EVENT_SHIFT);
 | |
| 		if (status & BIT(IS_S_RX_FIFO_FULL_SHIFT))
 | |
| 			val |= BIT(IS_S_RX_FIFO_FULL_SHIFT);
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, val);
 | |
| 	}
 | |
| 
 | |
| 	if (status & BIT(IS_S_TX_UNDERRUN_SHIFT)) {
 | |
| 		iproc_i2c->tx_underrun++;
 | |
| 		if (iproc_i2c->tx_underrun == 1)
 | |
| 			/* Start of SMBUS for Master Read */
 | |
| 			i2c_slave_event(iproc_i2c->slave,
 | |
| 					I2C_SLAVE_READ_REQUESTED,
 | |
| 					&value);
 | |
| 		else
 | |
| 			/* Master read other than start */
 | |
| 			i2c_slave_event(iproc_i2c->slave,
 | |
| 					I2C_SLAVE_READ_PROCESSED,
 | |
| 					&value);
 | |
| 
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value);
 | |
| 		/* start transfer */
 | |
| 		val = BIT(S_CMD_START_BUSY_SHIFT);
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val);
 | |
| 
 | |
| 		/* clear interrupt */
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET,
 | |
| 				 BIT(IS_S_TX_UNDERRUN_SHIFT));
 | |
| 	}
 | |
| 
 | |
| 	/* Stop received from master in case of master read transaction */
 | |
| 	if (status & BIT(IS_S_START_BUSY_SHIFT)) {
 | |
| 		/*
 | |
| 		 * Disable interrupt for TX FIFO becomes empty and
 | |
| 		 * less than PKT_LENGTH bytes were output on the SMBUS
 | |
| 		 */
 | |
| 		iproc_i2c->slave_int_mask &= ~BIT(IE_S_TX_UNDERRUN_SHIFT);
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET,
 | |
| 				 iproc_i2c->slave_int_mask);
 | |
| 
 | |
| 		/* End of SMBUS for Master Read */
 | |
| 		val = BIT(S_TX_WR_STATUS_SHIFT);
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, val);
 | |
| 
 | |
| 		val = BIT(S_CMD_START_BUSY_SHIFT);
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val);
 | |
| 
 | |
| 		/* flush TX FIFOs */
 | |
| 		val = iproc_i2c_rd_reg(iproc_i2c, S_FIFO_CTRL_OFFSET);
 | |
| 		val |= (BIT(S_FIFO_TX_FLUSH_SHIFT));
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val);
 | |
| 
 | |
| 		i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP, &value);
 | |
| 
 | |
| 		/* clear interrupt */
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET,
 | |
| 				 BIT(IS_S_START_BUSY_SHIFT));
 | |
| 	}
 | |
| 
 | |
| 	/* check slave transmit status only if slave is transmitting */
 | |
| 	if (!iproc_i2c->slave_rx_only)
 | |
| 		bcm_iproc_i2c_check_slave_status(iproc_i2c);
 | |
| 
 | |
| 	return true;
 | |
| }
 | |
| 
 | |
| static void bcm_iproc_i2c_read_valid_bytes(struct bcm_iproc_i2c_dev *iproc_i2c)
 | |
| {
 | |
| 	struct i2c_msg *msg = iproc_i2c->msg;
 | |
| 	uint32_t val;
 | |
| 
 | |
| 	/* Read valid data from RX FIFO */
 | |
| 	while (iproc_i2c->rx_bytes < msg->len) {
 | |
| 		val = iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET);
 | |
| 
 | |
| 		/* rx fifo empty */
 | |
| 		if (!((val >> M_RX_STATUS_SHIFT) & M_RX_STATUS_MASK))
 | |
| 			break;
 | |
| 
 | |
| 		msg->buf[iproc_i2c->rx_bytes] =
 | |
| 			(val >> M_RX_DATA_SHIFT) & M_RX_DATA_MASK;
 | |
| 		iproc_i2c->rx_bytes++;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void bcm_iproc_i2c_send(struct bcm_iproc_i2c_dev *iproc_i2c)
 | |
| {
 | |
| 	struct i2c_msg *msg = iproc_i2c->msg;
 | |
| 	unsigned int tx_bytes = msg->len - iproc_i2c->tx_bytes;
 | |
| 	unsigned int i;
 | |
| 	u32 val;
 | |
| 
 | |
| 	/* can only fill up to the FIFO size */
 | |
| 	tx_bytes = min_t(unsigned int, tx_bytes, M_TX_RX_FIFO_SIZE);
 | |
| 	for (i = 0; i < tx_bytes; i++) {
 | |
| 		/* start from where we left over */
 | |
| 		unsigned int idx = iproc_i2c->tx_bytes + i;
 | |
| 
 | |
| 		val = msg->buf[idx];
 | |
| 
 | |
| 		/* mark the last byte */
 | |
| 		if (idx == msg->len - 1) {
 | |
| 			val |= BIT(M_TX_WR_STATUS_SHIFT);
 | |
| 
 | |
| 			if (iproc_i2c->irq) {
 | |
| 				u32 tmp;
 | |
| 
 | |
| 				/*
 | |
| 				 * Since this is the last byte, we should now
 | |
| 				 * disable TX FIFO underrun interrupt
 | |
| 				 */
 | |
| 				tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
 | |
| 				tmp &= ~BIT(IE_M_TX_UNDERRUN_SHIFT);
 | |
| 				iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET,
 | |
| 						 tmp);
 | |
| 			}
 | |
| 		}
 | |
| 
 | |
| 		/* load data into TX FIFO */
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
 | |
| 	}
 | |
| 
 | |
| 	/* update number of transferred bytes */
 | |
| 	iproc_i2c->tx_bytes += tx_bytes;
 | |
| }
 | |
| 
 | |
| static void bcm_iproc_i2c_read(struct bcm_iproc_i2c_dev *iproc_i2c)
 | |
| {
 | |
| 	struct i2c_msg *msg = iproc_i2c->msg;
 | |
| 	u32 bytes_left, val;
 | |
| 
 | |
| 	bcm_iproc_i2c_read_valid_bytes(iproc_i2c);
 | |
| 	bytes_left = msg->len - iproc_i2c->rx_bytes;
 | |
| 	if (bytes_left == 0) {
 | |
| 		if (iproc_i2c->irq) {
 | |
| 			/* finished reading all data, disable rx thld event */
 | |
| 			val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
 | |
| 			val &= ~BIT(IS_M_RX_THLD_SHIFT);
 | |
| 			iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
 | |
| 		}
 | |
| 	} else if (bytes_left < iproc_i2c->thld_bytes) {
 | |
| 		/* set bytes left as threshold */
 | |
| 		val = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET);
 | |
| 		val &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT);
 | |
| 		val |= (bytes_left << M_FIFO_RX_THLD_SHIFT);
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
 | |
| 		iproc_i2c->thld_bytes = bytes_left;
 | |
| 	}
 | |
| 	/*
 | |
| 	 * bytes_left >= iproc_i2c->thld_bytes,
 | |
| 	 * hence no need to change the THRESHOLD SET.
 | |
| 	 * It will remain as iproc_i2c->thld_bytes itself
 | |
| 	 */
 | |
| }
 | |
| 
 | |
| static void bcm_iproc_i2c_process_m_event(struct bcm_iproc_i2c_dev *iproc_i2c,
 | |
| 					  u32 status)
 | |
| {
 | |
| 	/* TX FIFO is empty and we have more data to send */
 | |
| 	if (status & BIT(IS_M_TX_UNDERRUN_SHIFT))
 | |
| 		bcm_iproc_i2c_send(iproc_i2c);
 | |
| 
 | |
| 	/* RX FIFO threshold is reached and data needs to be read out */
 | |
| 	if (status & BIT(IS_M_RX_THLD_SHIFT))
 | |
| 		bcm_iproc_i2c_read(iproc_i2c);
 | |
| 
 | |
| 	/* transfer is done */
 | |
| 	if (status & BIT(IS_M_START_BUSY_SHIFT)) {
 | |
| 		iproc_i2c->xfer_is_done = 1;
 | |
| 		if (iproc_i2c->irq)
 | |
| 			complete(&iproc_i2c->done);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static irqreturn_t bcm_iproc_i2c_isr(int irq, void *data)
 | |
| {
 | |
| 	struct bcm_iproc_i2c_dev *iproc_i2c = data;
 | |
| 	u32 slave_status;
 | |
| 	u32 status;
 | |
| 	bool ret;
 | |
| 
 | |
| 	status = iproc_i2c_rd_reg(iproc_i2c, IS_OFFSET);
 | |
| 	/* process only slave interrupt which are enabled */
 | |
| 	slave_status = status & iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET) &
 | |
| 		       ISR_MASK_SLAVE;
 | |
| 
 | |
| 	if (slave_status) {
 | |
| 		ret = bcm_iproc_i2c_slave_isr(iproc_i2c, slave_status);
 | |
| 		if (ret)
 | |
| 			return IRQ_HANDLED;
 | |
| 		else
 | |
| 			return IRQ_NONE;
 | |
| 	}
 | |
| 
 | |
| 	status &= ISR_MASK;
 | |
| 	if (!status)
 | |
| 		return IRQ_NONE;
 | |
| 
 | |
| 	/* process all master based events */
 | |
| 	bcm_iproc_i2c_process_m_event(iproc_i2c, status);
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);
 | |
| 
 | |
| 	return IRQ_HANDLED;
 | |
| }
 | |
| 
 | |
| static int bcm_iproc_i2c_init(struct bcm_iproc_i2c_dev *iproc_i2c)
 | |
| {
 | |
| 	u32 val;
 | |
| 
 | |
| 	/* put controller in reset */
 | |
| 	val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
 | |
| 	val |= BIT(CFG_RESET_SHIFT);
 | |
| 	val &= ~(BIT(CFG_EN_SHIFT));
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
 | |
| 
 | |
| 	/* wait 100 usec per spec */
 | |
| 	udelay(100);
 | |
| 
 | |
| 	/* bring controller out of reset */
 | |
| 	val &= ~(BIT(CFG_RESET_SHIFT));
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
 | |
| 
 | |
| 	/* flush TX/RX FIFOs and set RX FIFO threshold to zero */
 | |
| 	val = (BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT));
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
 | |
| 	/* disable all interrupts */
 | |
| 	val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
 | |
| 	val &= ~(IE_M_ALL_INTERRUPT_MASK <<
 | |
| 			IE_M_ALL_INTERRUPT_SHIFT);
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
 | |
| 
 | |
| 	/* clear all pending interrupts */
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, 0xffffffff);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,
 | |
| 					 bool enable)
 | |
| {
 | |
| 	u32 val;
 | |
| 
 | |
| 	val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
 | |
| 	if (enable)
 | |
| 		val |= BIT(CFG_EN_SHIFT);
 | |
| 	else
 | |
| 		val &= ~BIT(CFG_EN_SHIFT);
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
 | |
| }
 | |
| 
 | |
| static int bcm_iproc_i2c_check_status(struct bcm_iproc_i2c_dev *iproc_i2c,
 | |
| 				      struct i2c_msg *msg)
 | |
| {
 | |
| 	u32 val;
 | |
| 
 | |
| 	val = iproc_i2c_rd_reg(iproc_i2c, M_CMD_OFFSET);
 | |
| 	val = (val >> M_CMD_STATUS_SHIFT) & M_CMD_STATUS_MASK;
 | |
| 
 | |
| 	switch (val) {
 | |
| 	case M_CMD_STATUS_SUCCESS:
 | |
| 		return 0;
 | |
| 
 | |
| 	case M_CMD_STATUS_LOST_ARB:
 | |
| 		dev_dbg(iproc_i2c->device, "lost bus arbitration\n");
 | |
| 		return -EAGAIN;
 | |
| 
 | |
| 	case M_CMD_STATUS_NACK_ADDR:
 | |
| 		dev_dbg(iproc_i2c->device, "NAK addr:0x%02x\n", msg->addr);
 | |
| 		return -ENXIO;
 | |
| 
 | |
| 	case M_CMD_STATUS_NACK_DATA:
 | |
| 		dev_dbg(iproc_i2c->device, "NAK data\n");
 | |
| 		return -ENXIO;
 | |
| 
 | |
| 	case M_CMD_STATUS_TIMEOUT:
 | |
| 		dev_dbg(iproc_i2c->device, "bus timeout\n");
 | |
| 		return -ETIMEDOUT;
 | |
| 
 | |
| 	case M_CMD_STATUS_FIFO_UNDERRUN:
 | |
| 		dev_dbg(iproc_i2c->device, "FIFO under-run\n");
 | |
| 		return -ENXIO;
 | |
| 
 | |
| 	case M_CMD_STATUS_RX_FIFO_FULL:
 | |
| 		dev_dbg(iproc_i2c->device, "RX FIFO full\n");
 | |
| 		return -ETIMEDOUT;
 | |
| 
 | |
| 	default:
 | |
| 		dev_dbg(iproc_i2c->device, "unknown error code=%d\n", val);
 | |
| 
 | |
| 		/* re-initialize i2c for recovery */
 | |
| 		bcm_iproc_i2c_enable_disable(iproc_i2c, false);
 | |
| 		bcm_iproc_i2c_init(iproc_i2c);
 | |
| 		bcm_iproc_i2c_enable_disable(iproc_i2c, true);
 | |
| 
 | |
| 		return -EIO;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c,
 | |
| 				   struct i2c_msg *msg,
 | |
| 				   u32 cmd)
 | |
| {
 | |
| 	unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT_MSEC);
 | |
| 	u32 val, status;
 | |
| 	int ret;
 | |
| 
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, M_CMD_OFFSET, cmd);
 | |
| 
 | |
| 	if (iproc_i2c->irq) {
 | |
| 		time_left = wait_for_completion_timeout(&iproc_i2c->done,
 | |
| 							time_left);
 | |
| 		/* disable all interrupts */
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
 | |
| 		/* read it back to flush the write */
 | |
| 		iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
 | |
| 		/* make sure the interrupt handler isn't running */
 | |
| 		synchronize_irq(iproc_i2c->irq);
 | |
| 
 | |
| 	} else { /* polling mode */
 | |
| 		unsigned long timeout = jiffies + time_left;
 | |
| 
 | |
| 		do {
 | |
| 			status = iproc_i2c_rd_reg(iproc_i2c,
 | |
| 						  IS_OFFSET) & ISR_MASK;
 | |
| 			bcm_iproc_i2c_process_m_event(iproc_i2c, status);
 | |
| 			iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);
 | |
| 
 | |
| 			if (time_after(jiffies, timeout)) {
 | |
| 				time_left = 0;
 | |
| 				break;
 | |
| 			}
 | |
| 
 | |
| 			cpu_relax();
 | |
| 			cond_resched();
 | |
| 		} while (!iproc_i2c->xfer_is_done);
 | |
| 	}
 | |
| 
 | |
| 	if (!time_left && !iproc_i2c->xfer_is_done) {
 | |
| 		dev_err(iproc_i2c->device, "transaction timed out\n");
 | |
| 
 | |
| 		/* flush both TX/RX FIFOs */
 | |
| 		val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
 | |
| 		return -ETIMEDOUT;
 | |
| 	}
 | |
| 
 | |
| 	ret = bcm_iproc_i2c_check_status(iproc_i2c, msg);
 | |
| 	if (ret) {
 | |
| 		/* flush both TX/RX FIFOs */
 | |
| 		val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * If 'process_call' is true, then this is a multi-msg transfer that requires
 | |
|  * a repeated start between the messages.
 | |
|  * More specifically, it must be a write (reg) followed by a read (data).
 | |
|  * The i2c quirks are set to enforce this rule.
 | |
|  */
 | |
| static int bcm_iproc_i2c_xfer_internal(struct bcm_iproc_i2c_dev *iproc_i2c,
 | |
| 					struct i2c_msg *msgs, bool process_call)
 | |
| {
 | |
| 	int i;
 | |
| 	u8 addr;
 | |
| 	u32 val, tmp, val_intr_en;
 | |
| 	unsigned int tx_bytes;
 | |
| 	struct i2c_msg *msg = &msgs[0];
 | |
| 
 | |
| 	/* check if bus is busy */
 | |
| 	if (!!(iproc_i2c_rd_reg(iproc_i2c,
 | |
| 				M_CMD_OFFSET) & BIT(M_CMD_START_BUSY_SHIFT))) {
 | |
| 		dev_warn(iproc_i2c->device, "bus is busy\n");
 | |
| 		return -EBUSY;
 | |
| 	}
 | |
| 
 | |
| 	iproc_i2c->msg = msg;
 | |
| 
 | |
| 	/* format and load slave address into the TX FIFO */
 | |
| 	addr = i2c_8bit_addr_from_msg(msg);
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, addr);
 | |
| 
 | |
| 	/*
 | |
| 	 * For a write transaction, load data into the TX FIFO. Only allow
 | |
| 	 * loading up to TX FIFO size - 1 bytes of data since the first byte
 | |
| 	 * has been used up by the slave address
 | |
| 	 */
 | |
| 	tx_bytes = min_t(unsigned int, msg->len, M_TX_RX_FIFO_SIZE - 1);
 | |
| 	if (!(msg->flags & I2C_M_RD)) {
 | |
| 		for (i = 0; i < tx_bytes; i++) {
 | |
| 			val = msg->buf[i];
 | |
| 
 | |
| 			/* mark the last byte */
 | |
| 			if (!process_call && (i == msg->len - 1))
 | |
| 				val |= BIT(M_TX_WR_STATUS_SHIFT);
 | |
| 
 | |
| 			iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
 | |
| 		}
 | |
| 		iproc_i2c->tx_bytes = tx_bytes;
 | |
| 	}
 | |
| 
 | |
| 	/* Process the read message if this is process call */
 | |
| 	if (process_call) {
 | |
| 		msg++;
 | |
| 		iproc_i2c->msg = msg;  /* point to second msg */
 | |
| 
 | |
| 		/*
 | |
| 		 * The last byte to be sent out should be a slave
 | |
| 		 * address with read operation
 | |
| 		 */
 | |
| 		addr = i2c_8bit_addr_from_msg(msg);
 | |
| 		/* mark it the last byte out */
 | |
| 		val = addr | BIT(M_TX_WR_STATUS_SHIFT);
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
 | |
| 	}
 | |
| 
 | |
| 	/* mark as incomplete before starting the transaction */
 | |
| 	if (iproc_i2c->irq)
 | |
| 		reinit_completion(&iproc_i2c->done);
 | |
| 
 | |
| 	iproc_i2c->xfer_is_done = 0;
 | |
| 
 | |
| 	/*
 | |
| 	 * Enable the "start busy" interrupt, which will be triggered after the
 | |
| 	 * transaction is done, i.e., the internal start_busy bit, transitions
 | |
| 	 * from 1 to 0.
 | |
| 	 */
 | |
| 	val_intr_en = BIT(IE_M_START_BUSY_SHIFT);
 | |
| 
 | |
| 	/*
 | |
| 	 * If TX data size is larger than the TX FIFO, need to enable TX
 | |
| 	 * underrun interrupt, which will be triggerred when the TX FIFO is
 | |
| 	 * empty. When that happens we can then pump more data into the FIFO
 | |
| 	 */
 | |
| 	if (!process_call && !(msg->flags & I2C_M_RD) &&
 | |
| 	    msg->len > iproc_i2c->tx_bytes)
 | |
| 		val_intr_en |= BIT(IE_M_TX_UNDERRUN_SHIFT);
 | |
| 
 | |
| 	/*
 | |
| 	 * Now we can activate the transfer. For a read operation, specify the
 | |
| 	 * number of bytes to read
 | |
| 	 */
 | |
| 	val = BIT(M_CMD_START_BUSY_SHIFT);
 | |
| 
 | |
| 	if (msg->len == 0) {
 | |
| 		/* SMBUS QUICK Command (Read/Write) */
 | |
| 		val |= (M_CMD_PROTOCOL_QUICK << M_CMD_PROTOCOL_SHIFT);
 | |
| 	} else if (msg->flags & I2C_M_RD) {
 | |
| 		u32 protocol;
 | |
| 
 | |
| 		iproc_i2c->rx_bytes = 0;
 | |
| 		if (msg->len > M_RX_FIFO_MAX_THLD_VALUE)
 | |
| 			iproc_i2c->thld_bytes = M_RX_FIFO_THLD_VALUE;
 | |
| 		else
 | |
| 			iproc_i2c->thld_bytes = msg->len;
 | |
| 
 | |
| 		/* set threshold value */
 | |
| 		tmp = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET);
 | |
| 		tmp &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT);
 | |
| 		tmp |= iproc_i2c->thld_bytes << M_FIFO_RX_THLD_SHIFT;
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, tmp);
 | |
| 
 | |
| 		/* enable the RX threshold interrupt */
 | |
| 		val_intr_en |= BIT(IE_M_RX_THLD_SHIFT);
 | |
| 
 | |
| 		protocol = process_call ?
 | |
| 				M_CMD_PROTOCOL_PROCESS : M_CMD_PROTOCOL_BLK_RD;
 | |
| 
 | |
| 		val |= (protocol << M_CMD_PROTOCOL_SHIFT) |
 | |
| 		       (msg->len << M_CMD_RD_CNT_SHIFT);
 | |
| 	} else {
 | |
| 		val |= (M_CMD_PROTOCOL_BLK_WR << M_CMD_PROTOCOL_SHIFT);
 | |
| 	}
 | |
| 
 | |
| 	if (iproc_i2c->irq)
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val_intr_en);
 | |
| 
 | |
| 	return bcm_iproc_i2c_xfer_wait(iproc_i2c, msg, val);
 | |
| }
 | |
| 
 | |
| static int bcm_iproc_i2c_xfer(struct i2c_adapter *adapter,
 | |
| 			      struct i2c_msg msgs[], int num)
 | |
| {
 | |
| 	struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adapter);
 | |
| 	bool process_call = false;
 | |
| 	int ret;
 | |
| 
 | |
| 	if (num == 2) {
 | |
| 		/* Repeated start, use process call */
 | |
| 		process_call = true;
 | |
| 		if (msgs[1].flags & I2C_M_NOSTART) {
 | |
| 			dev_err(iproc_i2c->device, "Invalid repeated start\n");
 | |
| 			return -EOPNOTSUPP;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	ret = bcm_iproc_i2c_xfer_internal(iproc_i2c, msgs, process_call);
 | |
| 	if (ret) {
 | |
| 		dev_dbg(iproc_i2c->device, "xfer failed\n");
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	return num;
 | |
| }
 | |
| 
 | |
| static uint32_t bcm_iproc_i2c_functionality(struct i2c_adapter *adap)
 | |
| {
 | |
| 	u32 val;
 | |
| 
 | |
| 	val = I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 | |
| 
 | |
| 	if (adap->algo->reg_slave)
 | |
| 		val |= I2C_FUNC_SLAVE;
 | |
| 
 | |
| 	return val;
 | |
| }
 | |
| 
 | |
| static struct i2c_algorithm bcm_iproc_algo = {
 | |
| 	.master_xfer = bcm_iproc_i2c_xfer,
 | |
| 	.functionality = bcm_iproc_i2c_functionality,
 | |
| 	.reg_slave = bcm_iproc_i2c_reg_slave,
 | |
| 	.unreg_slave = bcm_iproc_i2c_unreg_slave,
 | |
| };
 | |
| 
 | |
| static const struct i2c_adapter_quirks bcm_iproc_i2c_quirks = {
 | |
| 	.flags = I2C_AQ_COMB_WRITE_THEN_READ,
 | |
| 	.max_comb_1st_msg_len = M_TX_RX_FIFO_SIZE,
 | |
| 	.max_read_len = M_RX_MAX_READ_LEN,
 | |
| };
 | |
| 
 | |
| static int bcm_iproc_i2c_cfg_speed(struct bcm_iproc_i2c_dev *iproc_i2c)
 | |
| {
 | |
| 	unsigned int bus_speed;
 | |
| 	u32 val;
 | |
| 	int ret = of_property_read_u32(iproc_i2c->device->of_node,
 | |
| 				       "clock-frequency", &bus_speed);
 | |
| 	if (ret < 0) {
 | |
| 		dev_info(iproc_i2c->device,
 | |
| 			"unable to interpret clock-frequency DT property\n");
 | |
| 		bus_speed = I2C_MAX_STANDARD_MODE_FREQ;
 | |
| 	}
 | |
| 
 | |
| 	if (bus_speed < I2C_MAX_STANDARD_MODE_FREQ) {
 | |
| 		dev_err(iproc_i2c->device, "%d Hz bus speed not supported\n",
 | |
| 			bus_speed);
 | |
| 		dev_err(iproc_i2c->device,
 | |
| 			"valid speeds are 100khz and 400khz\n");
 | |
| 		return -EINVAL;
 | |
| 	} else if (bus_speed < I2C_MAX_FAST_MODE_FREQ) {
 | |
| 		bus_speed = I2C_MAX_STANDARD_MODE_FREQ;
 | |
| 	} else {
 | |
| 		bus_speed = I2C_MAX_FAST_MODE_FREQ;
 | |
| 	}
 | |
| 
 | |
| 	iproc_i2c->bus_speed = bus_speed;
 | |
| 	val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
 | |
| 	val &= ~BIT(TIM_CFG_MODE_400_SHIFT);
 | |
| 	val |= (bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT;
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
 | |
| 
 | |
| 	dev_info(iproc_i2c->device, "bus set to %u Hz\n", bus_speed);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int bcm_iproc_i2c_probe(struct platform_device *pdev)
 | |
| {
 | |
| 	int irq, ret = 0;
 | |
| 	struct bcm_iproc_i2c_dev *iproc_i2c;
 | |
| 	struct i2c_adapter *adap;
 | |
| 	struct resource *res;
 | |
| 
 | |
| 	iproc_i2c = devm_kzalloc(&pdev->dev, sizeof(*iproc_i2c),
 | |
| 				 GFP_KERNEL);
 | |
| 	if (!iproc_i2c)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	platform_set_drvdata(pdev, iproc_i2c);
 | |
| 	iproc_i2c->device = &pdev->dev;
 | |
| 	iproc_i2c->type =
 | |
| 		(enum bcm_iproc_i2c_type)of_device_get_match_data(&pdev->dev);
 | |
| 	init_completion(&iproc_i2c->done);
 | |
| 
 | |
| 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 | |
| 	iproc_i2c->base = devm_ioremap_resource(iproc_i2c->device, res);
 | |
| 	if (IS_ERR(iproc_i2c->base))
 | |
| 		return PTR_ERR(iproc_i2c->base);
 | |
| 
 | |
| 	if (iproc_i2c->type == IPROC_I2C_NIC) {
 | |
| 		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 | |
| 		iproc_i2c->idm_base = devm_ioremap_resource(iproc_i2c->device,
 | |
| 							    res);
 | |
| 		if (IS_ERR(iproc_i2c->idm_base))
 | |
| 			return PTR_ERR(iproc_i2c->idm_base);
 | |
| 
 | |
| 		ret = of_property_read_u32(iproc_i2c->device->of_node,
 | |
| 					   "brcm,ape-hsls-addr-mask",
 | |
| 					   &iproc_i2c->ape_addr_mask);
 | |
| 		if (ret < 0) {
 | |
| 			dev_err(iproc_i2c->device,
 | |
| 				"'brcm,ape-hsls-addr-mask' missing\n");
 | |
| 			return -EINVAL;
 | |
| 		}
 | |
| 
 | |
| 		spin_lock_init(&iproc_i2c->idm_lock);
 | |
| 
 | |
| 		/* no slave support */
 | |
| 		bcm_iproc_algo.reg_slave = NULL;
 | |
| 		bcm_iproc_algo.unreg_slave = NULL;
 | |
| 	}
 | |
| 
 | |
| 	ret = bcm_iproc_i2c_init(iproc_i2c);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	ret = bcm_iproc_i2c_cfg_speed(iproc_i2c);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	irq = platform_get_irq(pdev, 0);
 | |
| 	if (irq > 0) {
 | |
| 		ret = devm_request_irq(iproc_i2c->device, irq,
 | |
| 				       bcm_iproc_i2c_isr, 0, pdev->name,
 | |
| 				       iproc_i2c);
 | |
| 		if (ret < 0) {
 | |
| 			dev_err(iproc_i2c->device,
 | |
| 				"unable to request irq %i\n", irq);
 | |
| 			return ret;
 | |
| 		}
 | |
| 
 | |
| 		iproc_i2c->irq = irq;
 | |
| 	} else {
 | |
| 		dev_warn(iproc_i2c->device,
 | |
| 			 "no irq resource, falling back to poll mode\n");
 | |
| 	}
 | |
| 
 | |
| 	bcm_iproc_i2c_enable_disable(iproc_i2c, true);
 | |
| 
 | |
| 	adap = &iproc_i2c->adapter;
 | |
| 	i2c_set_adapdata(adap, iproc_i2c);
 | |
| 	snprintf(adap->name, sizeof(adap->name),
 | |
| 		"Broadcom iProc (%s)",
 | |
| 		of_node_full_name(iproc_i2c->device->of_node));
 | |
| 	adap->algo = &bcm_iproc_algo;
 | |
| 	adap->quirks = &bcm_iproc_i2c_quirks;
 | |
| 	adap->dev.parent = &pdev->dev;
 | |
| 	adap->dev.of_node = pdev->dev.of_node;
 | |
| 
 | |
| 	return i2c_add_adapter(adap);
 | |
| }
 | |
| 
 | |
| static int bcm_iproc_i2c_remove(struct platform_device *pdev)
 | |
| {
 | |
| 	struct bcm_iproc_i2c_dev *iproc_i2c = platform_get_drvdata(pdev);
 | |
| 
 | |
| 	if (iproc_i2c->irq) {
 | |
| 		/*
 | |
| 		 * Make sure there's no pending interrupt when we remove the
 | |
| 		 * adapter
 | |
| 		 */
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
 | |
| 		iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
 | |
| 		synchronize_irq(iproc_i2c->irq);
 | |
| 	}
 | |
| 
 | |
| 	i2c_del_adapter(&iproc_i2c->adapter);
 | |
| 	bcm_iproc_i2c_enable_disable(iproc_i2c, false);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| #ifdef CONFIG_PM_SLEEP
 | |
| 
 | |
| static int bcm_iproc_i2c_suspend(struct device *dev)
 | |
| {
 | |
| 	struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);
 | |
| 
 | |
| 	if (iproc_i2c->irq) {
 | |
| 		/*
 | |
| 		 * Make sure there's no pending interrupt when we go into
 | |
| 		 * suspend
 | |
| 		 */
 | |
| 		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
 | |
| 		iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
 | |
| 		synchronize_irq(iproc_i2c->irq);
 | |
| 	}
 | |
| 
 | |
| 	/* now disable the controller */
 | |
| 	bcm_iproc_i2c_enable_disable(iproc_i2c, false);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int bcm_iproc_i2c_resume(struct device *dev)
 | |
| {
 | |
| 	struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);
 | |
| 	int ret;
 | |
| 	u32 val;
 | |
| 
 | |
| 	/*
 | |
| 	 * Power domain could have been shut off completely in system deep
 | |
| 	 * sleep, so re-initialize the block here
 | |
| 	 */
 | |
| 	ret = bcm_iproc_i2c_init(iproc_i2c);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	/* configure to the desired bus speed */
 | |
| 	val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
 | |
| 	val &= ~BIT(TIM_CFG_MODE_400_SHIFT);
 | |
| 	val |= (iproc_i2c->bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT;
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
 | |
| 
 | |
| 	bcm_iproc_i2c_enable_disable(iproc_i2c, true);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static const struct dev_pm_ops bcm_iproc_i2c_pm_ops = {
 | |
| 	.suspend_late = &bcm_iproc_i2c_suspend,
 | |
| 	.resume_early = &bcm_iproc_i2c_resume
 | |
| };
 | |
| 
 | |
| #define BCM_IPROC_I2C_PM_OPS (&bcm_iproc_i2c_pm_ops)
 | |
| #else
 | |
| #define BCM_IPROC_I2C_PM_OPS NULL
 | |
| #endif /* CONFIG_PM_SLEEP */
 | |
| 
 | |
| 
 | |
| static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave)
 | |
| {
 | |
| 	struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter);
 | |
| 
 | |
| 	if (iproc_i2c->slave)
 | |
| 		return -EBUSY;
 | |
| 
 | |
| 	if (slave->flags & I2C_CLIENT_TEN)
 | |
| 		return -EAFNOSUPPORT;
 | |
| 
 | |
| 	iproc_i2c->slave = slave;
 | |
| 
 | |
| 	tasklet_init(&iproc_i2c->slave_rx_tasklet, slave_rx_tasklet_fn,
 | |
| 		     (unsigned long)iproc_i2c);
 | |
| 
 | |
| 	bcm_iproc_i2c_slave_init(iproc_i2c, false);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave)
 | |
| {
 | |
| 	u32 tmp;
 | |
| 	struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter);
 | |
| 
 | |
| 	if (!iproc_i2c->slave)
 | |
| 		return -EINVAL;
 | |
| 
 | |
| 	disable_irq(iproc_i2c->irq);
 | |
| 
 | |
| 	tasklet_kill(&iproc_i2c->slave_rx_tasklet);
 | |
| 
 | |
| 	/* disable all slave interrupts */
 | |
| 	tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
 | |
| 	tmp &= ~(IE_S_ALL_INTERRUPT_MASK <<
 | |
| 			IE_S_ALL_INTERRUPT_SHIFT);
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, tmp);
 | |
| 
 | |
| 	/* Erase the slave address programmed */
 | |
| 	tmp = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET);
 | |
| 	tmp &= ~BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT);
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, tmp);
 | |
| 
 | |
| 	/* flush TX/RX FIFOs */
 | |
| 	tmp = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT));
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, tmp);
 | |
| 
 | |
| 	/* clear all pending slave interrupts */
 | |
| 	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE);
 | |
| 
 | |
| 	iproc_i2c->slave = NULL;
 | |
| 
 | |
| 	enable_irq(iproc_i2c->irq);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static const struct of_device_id bcm_iproc_i2c_of_match[] = {
 | |
| 	{
 | |
| 		.compatible = "brcm,iproc-i2c",
 | |
| 		.data = (int *)IPROC_I2C,
 | |
| 	}, {
 | |
| 		.compatible = "brcm,iproc-nic-i2c",
 | |
| 		.data = (int *)IPROC_I2C_NIC,
 | |
| 	},
 | |
| 	{ /* sentinel */ }
 | |
| };
 | |
| MODULE_DEVICE_TABLE(of, bcm_iproc_i2c_of_match);
 | |
| 
 | |
| static struct platform_driver bcm_iproc_i2c_driver = {
 | |
| 	.driver = {
 | |
| 		.name = "bcm-iproc-i2c",
 | |
| 		.of_match_table = bcm_iproc_i2c_of_match,
 | |
| 		.pm = BCM_IPROC_I2C_PM_OPS,
 | |
| 	},
 | |
| 	.probe = bcm_iproc_i2c_probe,
 | |
| 	.remove = bcm_iproc_i2c_remove,
 | |
| };
 | |
| module_platform_driver(bcm_iproc_i2c_driver);
 | |
| 
 | |
| MODULE_AUTHOR("Ray Jui <rjui@broadcom.com>");
 | |
| MODULE_DESCRIPTION("Broadcom iProc I2C Driver");
 | |
| MODULE_LICENSE("GPL v2");
 |