diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-tegra.c')
-rw-r--r-- | drivers/i2c/busses/i2c-tegra.c | 136 |
1 files changed, 93 insertions, 43 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index ebaa78d17d6e..9fcb13beeb8f 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -54,20 +54,15 @@ #define I2C_INT_STATUS 0x068 #define I2C_INT_BUS_CLR_DONE BIT(11) #define I2C_INT_PACKET_XFER_COMPLETE BIT(7) -#define I2C_INT_ALL_PACKETS_XFER_COMPLETE BIT(6) -#define I2C_INT_TX_FIFO_OVERFLOW BIT(5) -#define I2C_INT_RX_FIFO_UNDERFLOW BIT(4) #define I2C_INT_NO_ACK BIT(3) #define I2C_INT_ARBITRATION_LOST BIT(2) #define I2C_INT_TX_FIFO_DATA_REQ BIT(1) #define I2C_INT_RX_FIFO_DATA_REQ BIT(0) #define I2C_CLK_DIVISOR 0x06c #define I2C_CLK_DIVISOR_STD_FAST_MODE_SHIFT 16 -#define I2C_CLK_MULTIPLIER_STD_FAST_MODE 8 #define DVC_CTRL_REG1 0x000 #define DVC_CTRL_REG1_INTR_EN BIT(10) -#define DVC_CTRL_REG2 0x004 #define DVC_CTRL_REG3 0x008 #define DVC_CTRL_REG3_SW_PROG BIT(26) #define DVC_CTRL_REG3_I2C_DONE_INTR_EN BIT(30) @@ -75,24 +70,22 @@ #define DVC_STATUS_I2C_DONE_INTR BIT(30) #define I2C_ERR_NONE 0x00 -#define I2C_ERR_NO_ACK 0x01 -#define I2C_ERR_ARBITRATION_LOST 0x02 -#define I2C_ERR_UNKNOWN_INTERRUPT 0x04 +#define I2C_ERR_NO_ACK BIT(0) +#define I2C_ERR_ARBITRATION_LOST BIT(1) +#define I2C_ERR_UNKNOWN_INTERRUPT BIT(2) +#define I2C_ERR_RX_BUFFER_OVERFLOW BIT(3) #define PACKET_HEADER0_HEADER_SIZE_SHIFT 28 #define PACKET_HEADER0_PACKET_ID_SHIFT 16 #define PACKET_HEADER0_CONT_ID_SHIFT 12 #define PACKET_HEADER0_PROTOCOL_I2C BIT(4) -#define I2C_HEADER_HIGHSPEED_MODE BIT(22) #define I2C_HEADER_CONT_ON_NAK BIT(21) -#define I2C_HEADER_SEND_START_BYTE BIT(20) #define I2C_HEADER_READ BIT(19) #define I2C_HEADER_10BIT_ADDR BIT(18) #define I2C_HEADER_IE_ENABLE BIT(17) #define I2C_HEADER_REPEAT_START BIT(16) #define I2C_HEADER_CONTINUE_XFER BIT(15) -#define I2C_HEADER_MASTER_ADDR_SHIFT 12 #define I2C_HEADER_SLAVE_ADDR_SHIFT 1 #define I2C_BUS_CLEAR_CNFG 0x084 @@ -106,8 +99,6 @@ #define I2C_CONFIG_LOAD 0x08C #define I2C_MSTR_CONFIG_LOAD BIT(0) -#define I2C_SLV_CONFIG_LOAD BIT(1) -#define I2C_TIMEOUT_CONFIG_LOAD BIT(2) #define I2C_CLKEN_OVERRIDE 0x090 #define I2C_MST_CORE_CLKEN_OVR BIT(0) @@ -133,7 +124,6 @@ #define I2C_STANDARD_MODE 100000 #define I2C_FAST_MODE 400000 #define I2C_FAST_PLUS_MODE 1000000 -#define I2C_HS_MODE 3500000 /* Packet header size in bytes */ #define I2C_PACKET_HEADER_SIZE 12 @@ -280,6 +270,7 @@ struct tegra_i2c_dev { u32 bus_clk_rate; u16 clk_divisor_non_hs_mode; bool is_multimaster_mode; + /* xfer_lock: lock to serialize transfer submission and processing */ spinlock_t xfer_lock; struct dma_chan *tx_dma_chan; struct dma_chan *rx_dma_chan; @@ -306,7 +297,7 @@ static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg) * to the I2C block inside the DVC block */ static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev, - unsigned long reg) + unsigned long reg) { if (i2c_dev->is_dvc) reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40; @@ -314,7 +305,7 @@ static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev, } static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val, - unsigned long reg) + unsigned long reg) { writel(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); @@ -329,13 +320,13 @@ static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg) } static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data, - unsigned long reg, int len) + unsigned long reg, int len) { writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); } static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data, - unsigned long reg, int len) + unsigned long reg, int len) { readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); } @@ -486,7 +477,7 @@ static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) dev_warn(i2c_dev->dev, "timeout waiting for fifo flush\n"); return -ETIMEDOUT; } - msleep(1); + usleep_range(1000, 2000); } return 0; } @@ -499,6 +490,13 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) size_t buf_remaining = i2c_dev->msg_buf_remaining; int words_to_transfer; + /* + * Catch overflow due to message fully sent + * before the check for RX FIFO availability. + */ + if (WARN_ON_ONCE(!(i2c_dev->msg_buf_remaining))) + return -EINVAL; + if (i2c_dev->hw->has_mst_fifo) { val = i2c_readl(i2c_dev, I2C_MST_FIFO_STATUS); rx_fifo_avail = (val & I2C_MST_FIFO_STATUS_RX_MASK) >> @@ -525,7 +523,11 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) * prevent overwriting past the end of buf */ if (rx_fifo_avail > 0 && buf_remaining > 0) { - BUG_ON(buf_remaining > 3); + /* + * buf_remaining > 3 check not needed as rx_fifo_avail == 0 + * when (words_to_transfer was > rx_fifo_avail) earlier + * in this function. + */ val = i2c_readl(i2c_dev, I2C_RX_FIFO); val = cpu_to_le32(val); memcpy(buf, &val, buf_remaining); @@ -533,7 +535,10 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) rx_fifo_avail--; } - BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0); + /* RX FIFO must be drained, otherwise it's an Overflow case. */ + if (WARN_ON_ONCE(rx_fifo_avail)) + return -EINVAL; + i2c_dev->msg_buf_remaining = buf_remaining; i2c_dev->msg_buf = buf; @@ -591,7 +596,11 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev) * boundary and fault. */ if (tx_fifo_avail > 0 && buf_remaining > 0) { - BUG_ON(buf_remaining > 3); + /* + * buf_remaining > 3 check not needed as tx_fifo_avail == 0 + * when (words_to_transfer was > tx_fifo_avail) earlier + * in this function for non-zero words_to_transfer. + */ memcpy(&val, buf, buf_remaining); val = le32_to_cpu(val); @@ -680,10 +689,11 @@ static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev) i2c_writel(i2c_dev, I2C_MSTR_CONFIG_LOAD, I2C_CONFIG_LOAD); if (in_interrupt()) err = readl_poll_timeout_atomic(addr, val, val == 0, - 1000, I2C_CONFIG_LOAD_TIMEOUT); + 1000, + I2C_CONFIG_LOAD_TIMEOUT); else - err = readl_poll_timeout(addr, val, val == 0, - 1000, I2C_CONFIG_LOAD_TIMEOUT); + err = readl_poll_timeout(addr, val, val == 0, 1000, + I2C_CONFIG_LOAD_TIMEOUT); if (err) { dev_warn(i2c_dev->dev, @@ -700,7 +710,7 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev, bool clk_reinit) u32 val; int err; u32 clk_divisor, clk_multiplier; - u32 tsu_thd = 0; + u32 tsu_thd; u8 tlow, thigh; err = pm_runtime_get_sync(i2c_dev->dev); @@ -856,10 +866,15 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) if (!i2c_dev->is_curr_dma_xfer) { if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) { - if (i2c_dev->msg_buf_remaining) - tegra_i2c_empty_rx_fifo(i2c_dev); - else - BUG(); + if (tegra_i2c_empty_rx_fifo(i2c_dev)) { + /* + * Overflow error condition: message fully sent, + * with no XFER_COMPLETE interrupt but hardware + * asks to transfer more. + */ + i2c_dev->msg_err |= I2C_ERR_RX_BUFFER_OVERFLOW; + goto err; + } } if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) { @@ -885,7 +900,14 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) if (status & I2C_INT_PACKET_XFER_COMPLETE) { if (i2c_dev->is_curr_dma_xfer) i2c_dev->msg_buf_remaining = 0; - BUG_ON(i2c_dev->msg_buf_remaining); + /* + * Underflow error condition: XFER_COMPLETE before message + * fully sent. + */ + if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining)) { + i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT; + goto err; + } complete(&i2c_dev->msg_complete); } goto done; @@ -1024,7 +1046,8 @@ static int tegra_i2c_issue_bus_clear(struct i2c_adapter *adap) } static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, - struct i2c_msg *msg, enum msg_end_type end_state) + struct i2c_msg *msg, + enum msg_end_type end_state) { u32 packet_header; u32 int_mask; @@ -1161,9 +1184,8 @@ unlock: if (err) return err; - time_left = wait_for_completion_timeout( - &i2c_dev->dma_complete, - msecs_to_jiffies(xfer_time)); + time_left = wait_for_completion_timeout(&i2c_dev->dma_complete, + msecs_to_jiffies(xfer_time)); if (time_left == 0) { dev_err(i2c_dev->dev, "DMA transfer timeout\n"); dmaengine_terminate_sync(i2c_dev->msg_read ? @@ -1225,11 +1247,11 @@ unlock: } static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], - int num) + int num) { struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); int i; - int ret = 0; + int ret; ret = pm_runtime_get_sync(i2c_dev->dev); if (ret < 0) { @@ -1271,14 +1293,15 @@ static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev) { struct device_node *np = i2c_dev->dev->of_node; int ret; + bool multi_mode; ret = of_property_read_u32(np, "clock-frequency", - &i2c_dev->bus_clk_rate); + &i2c_dev->bus_clk_rate); if (ret) i2c_dev->bus_clk_rate = 100000; /* default clock rate */ - i2c_dev->is_multimaster_mode = of_property_read_bool(np, - "multi-master"); + multi_mode = of_property_read_bool(np, "multi-master"); + i2c_dev->is_multimaster_mode = multi_mode; } static const struct i2c_algorithm tegra_i2c_algo = { @@ -1500,7 +1523,7 @@ static int tegra_i2c_probe(struct platform_device *pdev) void __iomem *base; phys_addr_t base_phys; int irq; - int ret = 0; + int ret; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); base_phys = res->start; @@ -1517,7 +1540,9 @@ static int tegra_i2c_probe(struct platform_device *pdev) div_clk = devm_clk_get(&pdev->dev, "div-clk"); if (IS_ERR(div_clk)) { - dev_err(&pdev->dev, "missing controller clock\n"); + if (PTR_ERR(div_clk) != -EPROBE_DEFER) + dev_err(&pdev->dev, "missing controller clock\n"); + return PTR_ERR(div_clk); } @@ -1622,7 +1647,7 @@ static int tegra_i2c_probe(struct platform_device *pdev) } ret = devm_request_irq(&pdev->dev, i2c_dev->irq, - tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev); + tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev); if (ret) { dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq); goto release_dma; @@ -1687,10 +1712,35 @@ static int tegra_i2c_remove(struct platform_device *pdev) } #ifdef CONFIG_PM_SLEEP +static int tegra_i2c_suspend(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&i2c_dev->adapter); + + return 0; +} + +static int tegra_i2c_resume(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int err; + + err = tegra_i2c_init(i2c_dev, false); + if (err) + return err; + + i2c_mark_adapter_resumed(&i2c_dev->adapter); + + return 0; +} + static const struct dev_pm_ops tegra_i2c_pm = { + SET_SYSTEM_SLEEP_PM_OPS(tegra_i2c_suspend, tegra_i2c_resume) SET_RUNTIME_PM_OPS(tegra_i2c_runtime_suspend, tegra_i2c_runtime_resume, NULL) }; + #define TEGRA_I2C_PM (&tegra_i2c_pm) #else #define TEGRA_I2C_PM NULL |