* [PATCH V19 1/7] i2c: tegra: sort all the include headers alphabetically @ 2019-02-12 18:28 Sowjanya Komatineni 2019-02-12 18:28 ` [PATCH V19 2/7] i2c: tegra: add bus clear Master Support Sowjanya Komatineni 0 siblings, 1 reply; 4+ messages in thread From: Sowjanya Komatineni @ 2019-02-12 18:28 UTC (permalink / raw) To: thierry.reding, jonathanh, mkarthik, smohammed, talho Cc: wsa, peda, digetx, linux-tegra, linux-kernel, linux-i2c, Sowjanya Komatineni This patch sorts all the include headers alphabetically for the I2C Tegra driver. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> --- [V9/V10/V11/V12/V13/V14/V15/V16/V17/V18/V19] : Rebased to 5.0-rc4 [V3/V4/V5/V7/V8] : Removed unsued headers in tegra I2C [V2] : Added this in V2 to sort the headers in tegra I2C drivers/i2c/busses/i2c-tegra.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index c77adbbea0c7..79c6aa87499b 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -6,24 +6,21 @@ * Author: Colin Cross <ccross@android.com> */ -#include <linux/kernel.h> -#include <linux/init.h> -#include <linux/platform_device.h> #include <linux/clk.h> +#include <linux/delay.h> #include <linux/err.h> #include <linux/i2c.h> -#include <linux/io.h> +#include <linux/init.h> #include <linux/interrupt.h> -#include <linux/delay.h> -#include <linux/slab.h> -#include <linux/of_device.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> #include <linux/module.h> -#include <linux/reset.h> +#include <linux/of_device.h> #include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> #include <linux/pm_runtime.h> -#include <linux/iopoll.h> - -#include <asm/unaligned.h> +#include <linux/reset.h> #define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000)) #define BYTES_PER_FIFO_WORD 4 -- 2.7.4 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH V19 2/7] i2c: tegra: add bus clear Master Support 2019-02-12 18:28 [PATCH V19 1/7] i2c: tegra: sort all the include headers alphabetically Sowjanya Komatineni @ 2019-02-12 18:28 ` Sowjanya Komatineni 0 siblings, 0 replies; 4+ messages in thread From: Sowjanya Komatineni @ 2019-02-12 18:28 UTC (permalink / raw) To: thierry.reding, jonathanh, mkarthik, smohammed, talho Cc: wsa, peda, digetx, linux-tegra, linux-kernel, linux-i2c, Sowjanya Komatineni Bus clear feature of Tegra I2C controller helps to recover from bus hang when I2C master loses the bus arbitration due to the slave device holding SDA LOW continuously for some unknown reasons. Per I2C specification, the device that held the bus LOW should release it within 9 clock pulses. During bus clear operation, Tegra I2C controller sends 9 clock pulses and terminates the transaction with STOP condition. Upon successful bus clear operation, bus goes to idle state and driver retries the transaction. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> --- [V19] : updated to use i2c bus recovery through i2c core adapter using i2c_bus_recovery_info [V9/V10/V11/V12/V13/V14/V15/V16/V17/V18] : Rebased to 5.0-rc4 [V5/V6/V7/V8] : Same as V4 [V4] : Added I2C Bus Clear support patch to this version of series. drivers/i2c/busses/i2c-tegra.c | 81 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 79c6aa87499b..a46446dbc48a 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -51,6 +51,7 @@ #define I2C_FIFO_STATUS_RX_SHIFT 0 #define I2C_INT_MASK 0x064 #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) @@ -93,6 +94,15 @@ #define I2C_HEADER_MASTER_ADDR_SHIFT 12 #define I2C_HEADER_SLAVE_ADDR_SHIFT 1 +#define I2C_BUS_CLEAR_CNFG 0x084 +#define I2C_BC_SCLK_THRESHOLD 9 +#define I2C_BC_SCLK_THRESHOLD_SHIFT 16 +#define I2C_BC_STOP_COND BIT(2) +#define I2C_BC_TERMINATE BIT(1) +#define I2C_BC_ENABLE BIT(0) +#define I2C_BUS_CLEAR_STATUS 0x088 +#define I2C_BC_STATUS BIT(0) + #define I2C_CONFIG_LOAD 0x08C #define I2C_MSTR_CONFIG_LOAD BIT(0) #define I2C_SLV_CONFIG_LOAD BIT(1) @@ -154,6 +164,8 @@ enum msg_end_type { * be transferred in one go. * @quirks: i2c adapter quirks for limiting write/read transfer size and not * allowing 0 length transfers. + * @supports_bus_clear: Bus Clear support to recover from bus hang during + * SDA stuck low from device for some unknown reasons. */ struct tegra_i2c_hw_feature { bool has_continue_xfer_support; @@ -167,6 +179,7 @@ struct tegra_i2c_hw_feature { bool has_slcg_override_reg; bool has_mst_fifo; const struct i2c_adapter_quirks *quirks; + bool supports_bus_clear; }; /** @@ -640,6 +653,13 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) goto err; } + /* + * I2C transfer is terminated during the bus clear so skip + * processing the other interrupts. + */ + if (i2c_dev->hw->supports_bus_clear && (status & I2C_INT_BUS_CLR_DONE)) + goto err; + 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); @@ -668,6 +688,8 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) tegra_i2c_mask_irq(i2c_dev, I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST | I2C_INT_PACKET_XFER_COMPLETE | I2C_INT_TX_FIFO_DATA_REQ | I2C_INT_RX_FIFO_DATA_REQ); + if (i2c_dev->hw->supports_bus_clear) + tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); i2c_writel(i2c_dev, status, I2C_INT_STATUS); if (i2c_dev->is_dvc) dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); @@ -678,6 +700,44 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) return IRQ_HANDLED; } +static int tegra_i2c_issue_bus_clear(struct i2c_adapter *adap) +{ + struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + int err; + unsigned long time_left; + u32 reg; + + reinit_completion(&i2c_dev->msg_complete); + reg = (I2C_BC_SCLK_THRESHOLD << I2C_BC_SCLK_THRESHOLD_SHIFT) | + I2C_BC_STOP_COND | I2C_BC_TERMINATE; + i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG); + if (i2c_dev->hw->has_config_load_reg) { + err = tegra_i2c_wait_for_config_load(i2c_dev); + if (err) + return err; + } + + reg |= I2C_BC_ENABLE; + i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG); + tegra_i2c_unmask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); + + time_left = wait_for_completion_timeout(&i2c_dev->msg_complete, + TEGRA_I2C_TIMEOUT); + if (time_left == 0) { + dev_err(i2c_dev->dev, "timed out for bus clear\n"); + return -ETIMEDOUT; + } + + reg = i2c_readl(i2c_dev, I2C_BUS_CLEAR_STATUS); + if (!(reg & I2C_BC_STATUS)) { + dev_err(i2c_dev->dev, + "un-recovered arbitration lost\n"); + return -EIO; + } + + return -EAGAIN; +} + static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, struct i2c_msg *msg, enum msg_end_type end_state) { @@ -759,6 +819,13 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, return 0; tegra_i2c_init(i2c_dev); + /* start recovery upon arbitration loss in single master mode */ + if (i2c_dev->msg_err == I2C_ERR_ARBITRATION_LOST) { + if (!i2c_dev->is_multimaster_mode) + return i2c_recover_bus(&i2c_dev->adapter); + return -EAGAIN; + } + if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { if (msg->flags & I2C_M_IGNORE_NAK) return 0; @@ -841,6 +908,10 @@ static const struct i2c_adapter_quirks tegra194_i2c_quirks = { .flags = I2C_AQ_NO_ZERO_LEN, }; +static struct i2c_bus_recovery_info tegra_i2c_recovery_info = { + .recover_bus = tegra_i2c_issue_bus_clear, +}; + static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { .has_continue_xfer_support = false, .has_per_pkt_xfer_complete_irq = false, @@ -853,6 +924,7 @@ static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, }; static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { @@ -867,6 +939,7 @@ static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, }; static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { @@ -881,6 +954,7 @@ static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, }; static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { @@ -895,6 +969,7 @@ static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { .has_slcg_override_reg = true, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, }; static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { @@ -909,6 +984,7 @@ static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { .has_slcg_override_reg = true, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, }; static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { @@ -923,6 +999,7 @@ static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { .has_slcg_override_reg = true, .has_mst_fifo = true, .quirks = &tegra194_i2c_quirks, + .supports_bus_clear = true, }; /* Match table for of_platform binding */ @@ -974,6 +1051,7 @@ static int tegra_i2c_probe(struct platform_device *pdev) i2c_dev->base = base; i2c_dev->div_clk = div_clk; i2c_dev->adapter.algo = &tegra_i2c_algo; + i2c_dev->adapter.retries = 1; i2c_dev->irq = irq; i2c_dev->cont_id = pdev->id; i2c_dev->dev = &pdev->dev; @@ -1051,6 +1129,9 @@ static int tegra_i2c_probe(struct platform_device *pdev) } } + if (i2c_dev->hw->supports_bus_clear) + i2c_dev->adapter.bus_recovery_info = &tegra_i2c_recovery_info; + ret = tegra_i2c_init(i2c_dev); if (ret) { dev_err(&pdev->dev, "Failed to initialize i2c controller\n"); -- 2.7.4 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH V19 1/7] i2c: tegra: sort all the include headers alphabetically @ 2019-02-12 19:06 Sowjanya Komatineni 2019-02-12 19:06 ` [PATCH V19 2/7] i2c: tegra: add bus clear Master Support Sowjanya Komatineni 0 siblings, 1 reply; 4+ messages in thread From: Sowjanya Komatineni @ 2019-02-12 19:06 UTC (permalink / raw) To: thierry.reding, jonathanh, mkarthik, smohammed, talho, skomatineni Cc: wsa, peda, digetx, linux-tegra, linux-kernel, linux-i2c This patch sorts all the include headers alphabetically for the I2C Tegra driver. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> --- [V9/V10/V11/V12/V13/V14/V15/V16/V17/V18/V19] : Rebased to 5.0-rc4 [V3/V4/V5/V7/V8] : Removed unsued headers in tegra I2C [V2] : Added this in V2 to sort the headers in tegra I2C drivers/i2c/busses/i2c-tegra.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index c77adbbea0c7..79c6aa87499b 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -6,24 +6,21 @@ * Author: Colin Cross <ccross@android.com> */ -#include <linux/kernel.h> -#include <linux/init.h> -#include <linux/platform_device.h> #include <linux/clk.h> +#include <linux/delay.h> #include <linux/err.h> #include <linux/i2c.h> -#include <linux/io.h> +#include <linux/init.h> #include <linux/interrupt.h> -#include <linux/delay.h> -#include <linux/slab.h> -#include <linux/of_device.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> #include <linux/module.h> -#include <linux/reset.h> +#include <linux/of_device.h> #include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> #include <linux/pm_runtime.h> -#include <linux/iopoll.h> - -#include <asm/unaligned.h> +#include <linux/reset.h> #define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000)) #define BYTES_PER_FIFO_WORD 4 -- 2.7.4 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH V19 2/7] i2c: tegra: add bus clear Master Support 2019-02-12 19:06 [PATCH V19 1/7] i2c: tegra: sort all the include headers alphabetically Sowjanya Komatineni @ 2019-02-12 19:06 ` Sowjanya Komatineni 0 siblings, 0 replies; 4+ messages in thread From: Sowjanya Komatineni @ 2019-02-12 19:06 UTC (permalink / raw) To: thierry.reding, jonathanh, mkarthik, smohammed, talho, skomatineni Cc: wsa, peda, digetx, linux-tegra, linux-kernel, linux-i2c Bus clear feature of Tegra I2C controller helps to recover from bus hang when I2C master loses the bus arbitration due to the slave device holding SDA LOW continuously for some unknown reasons. Per I2C specification, the device that held the bus LOW should release it within 9 clock pulses. During bus clear operation, Tegra I2C controller sends 9 clock pulses and terminates the transaction with STOP condition. Upon successful bus clear operation, bus goes to idle state and driver retries the transaction. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> --- [V19] : updated to use i2c bus recovery through i2c core adapter using i2c_bus_recovery_info [V9/V10/V11/V12/V13/V14/V15/V16/V17/V18] : Rebased to 5.0-rc4 [V5/V6/V7/V8] : Same as V4 [V4] : Added I2C Bus Clear support patch to this version of series. drivers/i2c/busses/i2c-tegra.c | 81 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 79c6aa87499b..a46446dbc48a 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -51,6 +51,7 @@ #define I2C_FIFO_STATUS_RX_SHIFT 0 #define I2C_INT_MASK 0x064 #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) @@ -93,6 +94,15 @@ #define I2C_HEADER_MASTER_ADDR_SHIFT 12 #define I2C_HEADER_SLAVE_ADDR_SHIFT 1 +#define I2C_BUS_CLEAR_CNFG 0x084 +#define I2C_BC_SCLK_THRESHOLD 9 +#define I2C_BC_SCLK_THRESHOLD_SHIFT 16 +#define I2C_BC_STOP_COND BIT(2) +#define I2C_BC_TERMINATE BIT(1) +#define I2C_BC_ENABLE BIT(0) +#define I2C_BUS_CLEAR_STATUS 0x088 +#define I2C_BC_STATUS BIT(0) + #define I2C_CONFIG_LOAD 0x08C #define I2C_MSTR_CONFIG_LOAD BIT(0) #define I2C_SLV_CONFIG_LOAD BIT(1) @@ -154,6 +164,8 @@ enum msg_end_type { * be transferred in one go. * @quirks: i2c adapter quirks for limiting write/read transfer size and not * allowing 0 length transfers. + * @supports_bus_clear: Bus Clear support to recover from bus hang during + * SDA stuck low from device for some unknown reasons. */ struct tegra_i2c_hw_feature { bool has_continue_xfer_support; @@ -167,6 +179,7 @@ struct tegra_i2c_hw_feature { bool has_slcg_override_reg; bool has_mst_fifo; const struct i2c_adapter_quirks *quirks; + bool supports_bus_clear; }; /** @@ -640,6 +653,13 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) goto err; } + /* + * I2C transfer is terminated during the bus clear so skip + * processing the other interrupts. + */ + if (i2c_dev->hw->supports_bus_clear && (status & I2C_INT_BUS_CLR_DONE)) + goto err; + 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); @@ -668,6 +688,8 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) tegra_i2c_mask_irq(i2c_dev, I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST | I2C_INT_PACKET_XFER_COMPLETE | I2C_INT_TX_FIFO_DATA_REQ | I2C_INT_RX_FIFO_DATA_REQ); + if (i2c_dev->hw->supports_bus_clear) + tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); i2c_writel(i2c_dev, status, I2C_INT_STATUS); if (i2c_dev->is_dvc) dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); @@ -678,6 +700,44 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) return IRQ_HANDLED; } +static int tegra_i2c_issue_bus_clear(struct i2c_adapter *adap) +{ + struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + int err; + unsigned long time_left; + u32 reg; + + reinit_completion(&i2c_dev->msg_complete); + reg = (I2C_BC_SCLK_THRESHOLD << I2C_BC_SCLK_THRESHOLD_SHIFT) | + I2C_BC_STOP_COND | I2C_BC_TERMINATE; + i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG); + if (i2c_dev->hw->has_config_load_reg) { + err = tegra_i2c_wait_for_config_load(i2c_dev); + if (err) + return err; + } + + reg |= I2C_BC_ENABLE; + i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG); + tegra_i2c_unmask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); + + time_left = wait_for_completion_timeout(&i2c_dev->msg_complete, + TEGRA_I2C_TIMEOUT); + if (time_left == 0) { + dev_err(i2c_dev->dev, "timed out for bus clear\n"); + return -ETIMEDOUT; + } + + reg = i2c_readl(i2c_dev, I2C_BUS_CLEAR_STATUS); + if (!(reg & I2C_BC_STATUS)) { + dev_err(i2c_dev->dev, + "un-recovered arbitration lost\n"); + return -EIO; + } + + return -EAGAIN; +} + static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, struct i2c_msg *msg, enum msg_end_type end_state) { @@ -759,6 +819,13 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, return 0; tegra_i2c_init(i2c_dev); + /* start recovery upon arbitration loss in single master mode */ + if (i2c_dev->msg_err == I2C_ERR_ARBITRATION_LOST) { + if (!i2c_dev->is_multimaster_mode) + return i2c_recover_bus(&i2c_dev->adapter); + return -EAGAIN; + } + if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { if (msg->flags & I2C_M_IGNORE_NAK) return 0; @@ -841,6 +908,10 @@ static const struct i2c_adapter_quirks tegra194_i2c_quirks = { .flags = I2C_AQ_NO_ZERO_LEN, }; +static struct i2c_bus_recovery_info tegra_i2c_recovery_info = { + .recover_bus = tegra_i2c_issue_bus_clear, +}; + static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { .has_continue_xfer_support = false, .has_per_pkt_xfer_complete_irq = false, @@ -853,6 +924,7 @@ static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, }; static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { @@ -867,6 +939,7 @@ static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, }; static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { @@ -881,6 +954,7 @@ static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, }; static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { @@ -895,6 +969,7 @@ static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { .has_slcg_override_reg = true, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, }; static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { @@ -909,6 +984,7 @@ static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { .has_slcg_override_reg = true, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, }; static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { @@ -923,6 +999,7 @@ static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { .has_slcg_override_reg = true, .has_mst_fifo = true, .quirks = &tegra194_i2c_quirks, + .supports_bus_clear = true, }; /* Match table for of_platform binding */ @@ -974,6 +1051,7 @@ static int tegra_i2c_probe(struct platform_device *pdev) i2c_dev->base = base; i2c_dev->div_clk = div_clk; i2c_dev->adapter.algo = &tegra_i2c_algo; + i2c_dev->adapter.retries = 1; i2c_dev->irq = irq; i2c_dev->cont_id = pdev->id; i2c_dev->dev = &pdev->dev; @@ -1051,6 +1129,9 @@ static int tegra_i2c_probe(struct platform_device *pdev) } } + if (i2c_dev->hw->supports_bus_clear) + i2c_dev->adapter.bus_recovery_info = &tegra_i2c_recovery_info; + ret = tegra_i2c_init(i2c_dev); if (ret) { dev_err(&pdev->dev, "Failed to initialize i2c controller\n"); -- 2.7.4 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH V19 1/7] i2c: tegra: sort all the include headers alphabetically @ 2019-02-12 18:27 Sowjanya Komatineni 2019-02-12 18:27 ` [PATCH V19 2/7] i2c: tegra: add bus clear Master Support Sowjanya Komatineni 0 siblings, 1 reply; 4+ messages in thread From: Sowjanya Komatineni @ 2019-02-12 18:27 UTC (permalink / raw) To: thierry.reding, jonathanh, mkarthik, smohammed, talho Cc: wsa, peda, digetx, linux-tegra, linux-kernel, linux-i2c, Sowjanya Komatineni This patch sorts all the include headers alphabetically for the I2C Tegra driver. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> --- [V9/V10/V11/V12/V13/V14/V15/V16/V17/V18/V19] : Rebased to 5.0-rc4 [V3/V4/V5/V7/V8] : Removed unsued headers in tegra I2C [V2] : Added this in V2 to sort the headers in tegra I2C drivers/i2c/busses/i2c-tegra.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index c77adbbea0c7..79c6aa87499b 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -6,24 +6,21 @@ * Author: Colin Cross <ccross@android.com> */ -#include <linux/kernel.h> -#include <linux/init.h> -#include <linux/platform_device.h> #include <linux/clk.h> +#include <linux/delay.h> #include <linux/err.h> #include <linux/i2c.h> -#include <linux/io.h> +#include <linux/init.h> #include <linux/interrupt.h> -#include <linux/delay.h> -#include <linux/slab.h> -#include <linux/of_device.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> #include <linux/module.h> -#include <linux/reset.h> +#include <linux/of_device.h> #include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> #include <linux/pm_runtime.h> -#include <linux/iopoll.h> - -#include <asm/unaligned.h> +#include <linux/reset.h> #define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000)) #define BYTES_PER_FIFO_WORD 4 -- 2.7.4 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH V19 2/7] i2c: tegra: add bus clear Master Support 2019-02-12 18:27 [PATCH V19 1/7] i2c: tegra: sort all the include headers alphabetically Sowjanya Komatineni @ 2019-02-12 18:27 ` Sowjanya Komatineni 0 siblings, 0 replies; 4+ messages in thread From: Sowjanya Komatineni @ 2019-02-12 18:27 UTC (permalink / raw) To: thierry.reding, jonathanh, mkarthik, smohammed, talho Cc: wsa, peda, digetx, linux-tegra, linux-kernel, linux-i2c, Sowjanya Komatineni Bus clear feature of Tegra I2C controller helps to recover from bus hang when I2C master loses the bus arbitration due to the slave device holding SDA LOW continuously for some unknown reasons. Per I2C specification, the device that held the bus LOW should release it within 9 clock pulses. During bus clear operation, Tegra I2C controller sends 9 clock pulses and terminates the transaction with STOP condition. Upon successful bus clear operation, bus goes to idle state and driver retries the transaction. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> --- [V19] : updated to use i2c bus recovery through i2c core adapter using i2c_bus_recovery_info [V9/V10/V11/V12/V13/V14/V15/V16/V17/V18] : Rebased to 5.0-rc4 [V5/V6/V7/V8] : Same as V4 [V4] : Added I2C Bus Clear support patch to this version of series. drivers/i2c/busses/i2c-tegra.c | 81 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 79c6aa87499b..a46446dbc48a 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -51,6 +51,7 @@ #define I2C_FIFO_STATUS_RX_SHIFT 0 #define I2C_INT_MASK 0x064 #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) @@ -93,6 +94,15 @@ #define I2C_HEADER_MASTER_ADDR_SHIFT 12 #define I2C_HEADER_SLAVE_ADDR_SHIFT 1 +#define I2C_BUS_CLEAR_CNFG 0x084 +#define I2C_BC_SCLK_THRESHOLD 9 +#define I2C_BC_SCLK_THRESHOLD_SHIFT 16 +#define I2C_BC_STOP_COND BIT(2) +#define I2C_BC_TERMINATE BIT(1) +#define I2C_BC_ENABLE BIT(0) +#define I2C_BUS_CLEAR_STATUS 0x088 +#define I2C_BC_STATUS BIT(0) + #define I2C_CONFIG_LOAD 0x08C #define I2C_MSTR_CONFIG_LOAD BIT(0) #define I2C_SLV_CONFIG_LOAD BIT(1) @@ -154,6 +164,8 @@ enum msg_end_type { * be transferred in one go. * @quirks: i2c adapter quirks for limiting write/read transfer size and not * allowing 0 length transfers. + * @supports_bus_clear: Bus Clear support to recover from bus hang during + * SDA stuck low from device for some unknown reasons. */ struct tegra_i2c_hw_feature { bool has_continue_xfer_support; @@ -167,6 +179,7 @@ struct tegra_i2c_hw_feature { bool has_slcg_override_reg; bool has_mst_fifo; const struct i2c_adapter_quirks *quirks; + bool supports_bus_clear; }; /** @@ -640,6 +653,13 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) goto err; } + /* + * I2C transfer is terminated during the bus clear so skip + * processing the other interrupts. + */ + if (i2c_dev->hw->supports_bus_clear && (status & I2C_INT_BUS_CLR_DONE)) + goto err; + 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); @@ -668,6 +688,8 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) tegra_i2c_mask_irq(i2c_dev, I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST | I2C_INT_PACKET_XFER_COMPLETE | I2C_INT_TX_FIFO_DATA_REQ | I2C_INT_RX_FIFO_DATA_REQ); + if (i2c_dev->hw->supports_bus_clear) + tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); i2c_writel(i2c_dev, status, I2C_INT_STATUS); if (i2c_dev->is_dvc) dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); @@ -678,6 +700,44 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) return IRQ_HANDLED; } +static int tegra_i2c_issue_bus_clear(struct i2c_adapter *adap) +{ + struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + int err; + unsigned long time_left; + u32 reg; + + reinit_completion(&i2c_dev->msg_complete); + reg = (I2C_BC_SCLK_THRESHOLD << I2C_BC_SCLK_THRESHOLD_SHIFT) | + I2C_BC_STOP_COND | I2C_BC_TERMINATE; + i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG); + if (i2c_dev->hw->has_config_load_reg) { + err = tegra_i2c_wait_for_config_load(i2c_dev); + if (err) + return err; + } + + reg |= I2C_BC_ENABLE; + i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG); + tegra_i2c_unmask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); + + time_left = wait_for_completion_timeout(&i2c_dev->msg_complete, + TEGRA_I2C_TIMEOUT); + if (time_left == 0) { + dev_err(i2c_dev->dev, "timed out for bus clear\n"); + return -ETIMEDOUT; + } + + reg = i2c_readl(i2c_dev, I2C_BUS_CLEAR_STATUS); + if (!(reg & I2C_BC_STATUS)) { + dev_err(i2c_dev->dev, + "un-recovered arbitration lost\n"); + return -EIO; + } + + return -EAGAIN; +} + static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, struct i2c_msg *msg, enum msg_end_type end_state) { @@ -759,6 +819,13 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, return 0; tegra_i2c_init(i2c_dev); + /* start recovery upon arbitration loss in single master mode */ + if (i2c_dev->msg_err == I2C_ERR_ARBITRATION_LOST) { + if (!i2c_dev->is_multimaster_mode) + return i2c_recover_bus(&i2c_dev->adapter); + return -EAGAIN; + } + if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { if (msg->flags & I2C_M_IGNORE_NAK) return 0; @@ -841,6 +908,10 @@ static const struct i2c_adapter_quirks tegra194_i2c_quirks = { .flags = I2C_AQ_NO_ZERO_LEN, }; +static struct i2c_bus_recovery_info tegra_i2c_recovery_info = { + .recover_bus = tegra_i2c_issue_bus_clear, +}; + static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { .has_continue_xfer_support = false, .has_per_pkt_xfer_complete_irq = false, @@ -853,6 +924,7 @@ static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, }; static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { @@ -867,6 +939,7 @@ static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, }; static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { @@ -881,6 +954,7 @@ static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, }; static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { @@ -895,6 +969,7 @@ static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { .has_slcg_override_reg = true, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, }; static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { @@ -909,6 +984,7 @@ static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { .has_slcg_override_reg = true, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, }; static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { @@ -923,6 +999,7 @@ static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { .has_slcg_override_reg = true, .has_mst_fifo = true, .quirks = &tegra194_i2c_quirks, + .supports_bus_clear = true, }; /* Match table for of_platform binding */ @@ -974,6 +1051,7 @@ static int tegra_i2c_probe(struct platform_device *pdev) i2c_dev->base = base; i2c_dev->div_clk = div_clk; i2c_dev->adapter.algo = &tegra_i2c_algo; + i2c_dev->adapter.retries = 1; i2c_dev->irq = irq; i2c_dev->cont_id = pdev->id; i2c_dev->dev = &pdev->dev; @@ -1051,6 +1129,9 @@ static int tegra_i2c_probe(struct platform_device *pdev) } } + if (i2c_dev->hw->supports_bus_clear) + i2c_dev->adapter.bus_recovery_info = &tegra_i2c_recovery_info; + ret = tegra_i2c_init(i2c_dev); if (ret) { dev_err(&pdev->dev, "Failed to initialize i2c controller\n"); -- 2.7.4 ^ permalink raw reply related [flat|nested] 4+ messages in thread
end of thread, other threads:[~2019-02-12 19:06 UTC | newest] Thread overview: 4+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2019-02-12 18:28 [PATCH V19 1/7] i2c: tegra: sort all the include headers alphabetically Sowjanya Komatineni 2019-02-12 18:28 ` [PATCH V19 2/7] i2c: tegra: add bus clear Master Support Sowjanya Komatineni -- strict thread matches above, loose matches on Subject: below -- 2019-02-12 19:06 [PATCH V19 1/7] i2c: tegra: sort all the include headers alphabetically Sowjanya Komatineni 2019-02-12 19:06 ` [PATCH V19 2/7] i2c: tegra: add bus clear Master Support Sowjanya Komatineni 2019-02-12 18:27 [PATCH V19 1/7] i2c: tegra: sort all the include headers alphabetically Sowjanya Komatineni 2019-02-12 18:27 ` [PATCH V19 2/7] i2c: tegra: add bus clear Master Support Sowjanya Komatineni
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