From 98be694ba25fa0e87811e7784b782c9498741b26 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Fri, 9 Nov 2018 18:02:16 +0100 Subject: i2c: nvidia-gpu: adhere to I2C fault codes As described in Documentation/i2c/fault-codes. Signed-off-by: Wolfram Sang Fixes: c71bcdcb42a7 ("i2c: add i2c bus driver for NVIDIA GPU") Acked-by: Ajay Gupta Tested-by: Ajay Gupta --- drivers/i2c/busses/i2c-nvidia-gpu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-nvidia-gpu.c b/drivers/i2c/busses/i2c-nvidia-gpu.c index 8822357bca0c..4307b42901a1 100644 --- a/drivers/i2c/busses/i2c-nvidia-gpu.c +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c @@ -89,7 +89,7 @@ static int gpu_i2c_check_status(struct gpu_i2c_dev *i2cd) if (time_is_before_jiffies(target)) { dev_err(i2cd->dev, "i2c timeout error %x\n", val); - return -ETIME; + return -ETIMEDOUT; } val = readl(i2cd->regs + I2C_MST_CNTL); @@ -97,9 +97,9 @@ static int gpu_i2c_check_status(struct gpu_i2c_dev *i2cd) case I2C_MST_CNTL_STATUS_OKAY: return 0; case I2C_MST_CNTL_STATUS_NO_ACK: - return -EIO; + return -ENXIO; case I2C_MST_CNTL_STATUS_TIMEOUT: - return -ETIME; + return -ETIMEDOUT; default: return 0; } -- cgit v1.2.3 From 39129f28c9431522a6790e7b8c3283221a28447b Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Fri, 9 Nov 2018 18:07:32 +0100 Subject: i2c: nvidia-gpu: limit reads also for combined messages If the controller can only do 4 byte reads, this needs to be applied for the read-part of combined messages, too. Signed-off-by: Wolfram Sang Fixes: c71bcdcb42a7 ("i2c: add i2c bus driver for NVIDIA GPU") Acked-by: Ajay Gupta Tested-by: Ajay Gupta --- drivers/i2c/busses/i2c-nvidia-gpu.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-nvidia-gpu.c b/drivers/i2c/busses/i2c-nvidia-gpu.c index 4307b42901a1..e99c3bb58351 100644 --- a/drivers/i2c/busses/i2c-nvidia-gpu.c +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c @@ -218,6 +218,7 @@ stop: static const struct i2c_adapter_quirks gpu_i2c_quirks = { .max_read_len = 4, + .max_comb_2nd_msg_len = 4, .flags = I2C_AQ_COMB_WRITE_THEN_READ, }; -- cgit v1.2.3 From 0b57436f15bf40e432487086c4f2d01fd3529393 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Tue, 13 Nov 2018 12:15:42 +0100 Subject: i2c: rcar: check bus state before reinitializing We should check the bus state before reinitializing the IP core. Otherwise, the internal bus busy state which also tracks multi-master activity is lost. Credits go to the Renesas BSP team for suggesting this change. Reported-by: Yoshihiro Shimoda Signed-off-by: Wolfram Sang Fixes: ae481cc13965 ("i2c: rcar: fix resume by always initializing registers before transfer") Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-rcar.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index 4aa7dde876f3..254e6219e538 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -779,6 +779,11 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap, pm_runtime_get_sync(dev); + /* Check bus state before init otherwise bus busy info will be lost */ + ret = rcar_i2c_bus_barrier(priv); + if (ret < 0) + goto out; + /* Gen3 needs a reset before allowing RXDMA once */ if (priv->devtype == I2C_RCAR_GEN3) { priv->flags |= ID_P_NO_RXDMA; @@ -791,10 +796,6 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap, rcar_i2c_init(priv); - ret = rcar_i2c_bus_barrier(priv); - if (ret < 0) - goto out; - for (i = 0; i < num; i++) rcar_i2c_request_dma(priv, msgs + i); -- cgit v1.2.3 From 6c7f25cae54b840302e4f1b371dbf318fbf09ab2 Mon Sep 17 00:00:00 2001 From: "Adamski, Krzysztof (Nokia - PL/Wroclaw)" Date: Fri, 16 Nov 2018 13:24:41 +0000 Subject: i2c: axxia: properly handle master timeout According to Intel (R) Axxia TM Lionfish Communication Processor Peripheral Subsystem Hardware Reference Manual, the AXXIA I2C module have a programmable Master Wait Timer, which among others, checks the time between commands send in manual mode. When a timeout (25ms) passes, TSS bit is set in Master Interrupt Status register and a Stop command is issued by the hardware. The axxia_i2c_xfer(), does not properly handle this situation, however. For each message a separate axxia_i2c_xfer_msg() is called and this function incorrectly assumes that any interrupt might happen only when waiting for completion. This is mostly correct but there is one exception - a master timeout can trigger if enough time has passed between individual transfers. It will, by definition, happen between transfers when the interrupts are disabled by the code. If that happens, the hardware issues Stop command. The interrupt indicating timeout will not be triggered as soon as we enable them since the Master Interrupt Status is cleared when master mode is entered again (which happens before enabling irqs) meaning this error is lost and the transfer is continued even though the Stop was issued on the bus. The subsequent operations completes without error but a bogus value (0xFF in case of read) is read as the client device is confused because aborted transfer. No error is returned from master_xfer() making caller believe that a valid value was read. To fix the problem, the TSS bit (indicating timeout) in Master Interrupt Status register is checked before each transfer. If it is set, there was a timeout before this transfer and (as described above) the hardware already issued Stop command so the transaction should be aborted thus -ETIMEOUT is returned from the master_xfer() callback. In order to be sure no timeout was issued we can't just read the status just before starting new transaction as there will always be a small window of time (few CPU cycles at best) where this might still happen. For this reason we have to temporally disable the timer before checking for TSS bit. Disabling it will, however, clear the TSS bit so in order to preserve that information, we have to read it in ISR so we have to ensure that the TSS interrupt is not masked between transfers of one transaction. There is no need to call bus recovery or controller reinitialization if that happens so it's skipped. Signed-off-by: Krzysztof Adamski Reviewed-by: Alexander Sverdlin Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-axxia.c | 40 +++++++++++++++++++++++++++++----------- 1 file changed, 29 insertions(+), 11 deletions(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-axxia.c b/drivers/i2c/busses/i2c-axxia.c index 8e60048a33f8..51d34959709b 100644 --- a/drivers/i2c/busses/i2c-axxia.c +++ b/drivers/i2c/busses/i2c-axxia.c @@ -74,8 +74,7 @@ MST_STATUS_ND) #define MST_STATUS_ERR (MST_STATUS_NAK | \ MST_STATUS_AL | \ - MST_STATUS_IP | \ - MST_STATUS_TSS) + MST_STATUS_IP) #define MST_TX_BYTES_XFRD 0x50 #define MST_RX_BYTES_XFRD 0x54 #define SCL_HIGH_PERIOD 0x80 @@ -241,7 +240,7 @@ static int axxia_i2c_empty_rx_fifo(struct axxia_i2c_dev *idev) */ if (c <= 0 || c > I2C_SMBUS_BLOCK_MAX) { idev->msg_err = -EPROTO; - i2c_int_disable(idev, ~0); + i2c_int_disable(idev, ~MST_STATUS_TSS); complete(&idev->msg_complete); break; } @@ -299,14 +298,19 @@ static irqreturn_t axxia_i2c_isr(int irq, void *_dev) if (status & MST_STATUS_SCC) { /* Stop completed */ - i2c_int_disable(idev, ~0); + i2c_int_disable(idev, ~MST_STATUS_TSS); complete(&idev->msg_complete); } else if (status & MST_STATUS_SNS) { /* Transfer done */ - i2c_int_disable(idev, ~0); + i2c_int_disable(idev, ~MST_STATUS_TSS); if (i2c_m_rd(idev->msg) && idev->msg_xfrd < idev->msg->len) axxia_i2c_empty_rx_fifo(idev); complete(&idev->msg_complete); + } else if (status & MST_STATUS_TSS) { + /* Transfer timeout */ + idev->msg_err = -ETIMEDOUT; + i2c_int_disable(idev, ~MST_STATUS_TSS); + complete(&idev->msg_complete); } else if (unlikely(status & MST_STATUS_ERR)) { /* Transfer error */ i2c_int_disable(idev, ~0); @@ -339,10 +343,10 @@ static int axxia_i2c_xfer_msg(struct axxia_i2c_dev *idev, struct i2c_msg *msg) u32 rx_xfer, tx_xfer; u32 addr_1, addr_2; unsigned long time_left; + unsigned int wt_value; idev->msg = msg; idev->msg_xfrd = 0; - idev->msg_err = 0; reinit_completion(&idev->msg_complete); if (i2c_m_ten(msg)) { @@ -383,9 +387,18 @@ static int axxia_i2c_xfer_msg(struct axxia_i2c_dev *idev, struct i2c_msg *msg) else if (axxia_i2c_fill_tx_fifo(idev) != 0) int_mask |= MST_STATUS_TFL; + wt_value = WT_VALUE(readl(idev->base + WAIT_TIMER_CONTROL)); + /* Disable wait timer temporarly */ + writel(wt_value, idev->base + WAIT_TIMER_CONTROL); + /* Check if timeout error happened */ + if (idev->msg_err) + goto out; + /* Start manual mode */ writel(CMD_MANUAL, idev->base + MST_COMMAND); + writel(WT_EN | wt_value, idev->base + WAIT_TIMER_CONTROL); + i2c_int_enable(idev, int_mask); time_left = wait_for_completion_timeout(&idev->msg_complete, @@ -396,13 +409,15 @@ static int axxia_i2c_xfer_msg(struct axxia_i2c_dev *idev, struct i2c_msg *msg) if (readl(idev->base + MST_COMMAND) & CMD_BUSY) dev_warn(idev->dev, "busy after xfer\n"); - if (time_left == 0) + if (time_left == 0) { idev->msg_err = -ETIMEDOUT; - - if (idev->msg_err == -ETIMEDOUT) i2c_recover_bus(&idev->adapter); + axxia_i2c_init(idev); + } - if (unlikely(idev->msg_err) && idev->msg_err != -ENXIO) +out: + if (unlikely(idev->msg_err) && idev->msg_err != -ENXIO && + idev->msg_err != -ETIMEDOUT) axxia_i2c_init(idev); return idev->msg_err; @@ -410,7 +425,7 @@ static int axxia_i2c_xfer_msg(struct axxia_i2c_dev *idev, struct i2c_msg *msg) static int axxia_i2c_stop(struct axxia_i2c_dev *idev) { - u32 int_mask = MST_STATUS_ERR | MST_STATUS_SCC; + u32 int_mask = MST_STATUS_ERR | MST_STATUS_SCC | MST_STATUS_TSS; unsigned long time_left; reinit_completion(&idev->msg_complete); @@ -437,6 +452,9 @@ axxia_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) int i; int ret = 0; + idev->msg_err = 0; + i2c_int_enable(idev, MST_STATUS_TSS); + for (i = 0; ret == 0 && i < num; ++i) ret = axxia_i2c_xfer_msg(idev, &msgs[i]); -- cgit v1.2.3 From 0544ee4b1ad574aec3b6379af5f5cdee42840971 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Wed, 21 Nov 2018 10:19:55 +0100 Subject: i2c: scmi: Fix probe error on devices with an empty SMB0001 ACPI device node Some AMD based HP laptops have a SMB0001 ACPI device node which does not define any methods. This leads to the following error in dmesg: [ 5.222731] cmi: probe of SMB0001:00 failed with error -5 This commit makes acpi_smbus_cmi_add() return -ENODEV instead in this case silencing the error. In case of a failure of the i2c_add_adapter() call this commit now propagates the error from that call instead of -EIO. Signed-off-by: Hans de Goede Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-scmi.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-scmi.c b/drivers/i2c/busses/i2c-scmi.c index 7e9a2bbf5ddc..ff3f4553648f 100644 --- a/drivers/i2c/busses/i2c-scmi.c +++ b/drivers/i2c/busses/i2c-scmi.c @@ -367,6 +367,7 @@ static int acpi_smbus_cmi_add(struct acpi_device *device) { struct acpi_smbus_cmi *smbus_cmi; const struct acpi_device_id *id; + int ret; smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL); if (!smbus_cmi) @@ -388,8 +389,10 @@ static int acpi_smbus_cmi_add(struct acpi_device *device) acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1, acpi_smbus_cmi_query_methods, NULL, smbus_cmi, NULL); - if (smbus_cmi->cap_info == 0) + if (smbus_cmi->cap_info == 0) { + ret = -ENODEV; goto err; + } snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name), "SMBus CMI adapter %s", @@ -400,7 +403,8 @@ static int acpi_smbus_cmi_add(struct acpi_device *device) smbus_cmi->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; smbus_cmi->adapter.dev.parent = &device->dev; - if (i2c_add_adapter(&smbus_cmi->adapter)) { + ret = i2c_add_adapter(&smbus_cmi->adapter); + if (ret) { dev_err(&device->dev, "Couldn't register adapter!\n"); goto err; } @@ -410,7 +414,7 @@ static int acpi_smbus_cmi_add(struct acpi_device *device) err: kfree(smbus_cmi); device->driver_data = NULL; - return -EIO; + return ret; } static int acpi_smbus_cmi_remove(struct acpi_device *device) -- cgit v1.2.3 From c2a653deaa81f5a750c0dfcbaf9f8e5195cbe4a5 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 6 Dec 2018 12:55:25 +0900 Subject: i2c: uniphier-f: fix timeout error after reading 8 bytes I was totally screwed up in commit eaba68785c2d ("i2c: uniphier-f: fix race condition when IRQ is cleared"). Since that commit, if the number of read bytes is multiple of the FIFO size (8, 16, 24... bytes), the STOP condition could be issued twice, depending on the timing. If this happens, the controller will go wrong, resulting in the timeout error. It was more than 3 years ago when I wrote this driver, so my memory about this hardware was vague. Please let me correct the description in the commit log of eaba68785c2d. Clearing the IRQ status on exiting the IRQ handler is absolutely fine. This controller makes a pause while any IRQ status is asserted. If the IRQ status is cleared first, the hardware may start the next transaction before the IRQ handler finishes what it supposed to do. This partially reverts the bad commit with clear comments so that I will never repeat this mistake. I also investigated what is happening at the last moment of the read mode. The UNIPHIER_FI2C_INT_RF interrupt is asserted a bit earlier (by half a period of the clock cycle) than UNIPHIER_FI2C_INT_RB. I consulted a hardware engineer, and I got the following information: UNIPHIER_FI2C_INT_RF asserted at the falling edge of SCL at the 8th bit. UNIPHIER_FI2C_INT_RB asserted at the rising edge of SCL at the 9th (ACK) bit. In order to avoid calling uniphier_fi2c_stop() twice, check the latter interrupt. I also commented this because it is obscure hardware internal. Fixes: eaba68785c2d ("i2c: uniphier-f: fix race condition when IRQ is cleared") Signed-off-by: Masahiro Yamada Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-uniphier-f.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c index dd384743dbbd..fad2b00a8c8c 100644 --- a/drivers/i2c/busses/i2c-uniphier-f.c +++ b/drivers/i2c/busses/i2c-uniphier-f.c @@ -173,8 +173,6 @@ static irqreturn_t uniphier_fi2c_interrupt(int irq, void *dev_id) "interrupt: enabled_irqs=%04x, irq_status=%04x\n", priv->enabled_irqs, irq_status); - uniphier_fi2c_clear_irqs(priv, irq_status); - if (irq_status & UNIPHIER_FI2C_INT_STOP) goto complete; @@ -214,7 +212,13 @@ static irqreturn_t uniphier_fi2c_interrupt(int irq, void *dev_id) if (irq_status & (UNIPHIER_FI2C_INT_RF | UNIPHIER_FI2C_INT_RB)) { uniphier_fi2c_drain_rxfifo(priv); - if (!priv->len) + /* + * If the number of bytes to read is multiple of the FIFO size + * (msg->len == 8, 16, 24, ...), the INT_RF bit is set a little + * earlier than INT_RB. We wait for INT_RB to confirm the + * completion of the current message. + */ + if (!priv->len && (irq_status & UNIPHIER_FI2C_INT_RB)) goto data_done; if (unlikely(priv->flags & UNIPHIER_FI2C_MANUAL_NACK)) { @@ -253,6 +257,13 @@ complete: } handled: + /* + * This controller makes a pause while any bit of the IRQ status is + * asserted. Clear the asserted bit to kick the controller just before + * exiting the handler. + */ + uniphier_fi2c_clear_irqs(priv, irq_status); + spin_unlock(&priv->lock); return IRQ_HANDLED; -- cgit v1.2.3 From cd8843f541cc0ef057e27f1afba46374bbb84219 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 6 Dec 2018 12:55:26 +0900 Subject: i2c: uniphier-f: fill TX-FIFO only in IRQ handler for repeated START - For a repeated START condition, this controller starts data transfer immediately after the slave address is written to the TX-FIFO. - Once the TX-FIFO empty interrupt is asserted, the controller makes a pause even if additional data are written to the TX-FIFO. Given those circumstances, the data after a repeated START may not be transferred if the interrupt is asserted while the TX-FIFO is being filled up. A more reliable way is to append TX data only in the interrupt handler. Signed-off-by: Masahiro Yamada Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-uniphier-f.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c index fad2b00a8c8c..d8a5db14da79 100644 --- a/drivers/i2c/busses/i2c-uniphier-f.c +++ b/drivers/i2c/busses/i2c-uniphier-f.c @@ -269,7 +269,8 @@ handled: return IRQ_HANDLED; } -static void uniphier_fi2c_tx_init(struct uniphier_fi2c_priv *priv, u16 addr) +static void uniphier_fi2c_tx_init(struct uniphier_fi2c_priv *priv, u16 addr, + bool repeat) { priv->enabled_irqs |= UNIPHIER_FI2C_INT_TE; uniphier_fi2c_set_irqs(priv); @@ -279,8 +280,12 @@ static void uniphier_fi2c_tx_init(struct uniphier_fi2c_priv *priv, u16 addr) /* set slave address */ writel(UNIPHIER_FI2C_DTTX_CMD | addr << 1, priv->membase + UNIPHIER_FI2C_DTTX); - /* first chunk of data */ - uniphier_fi2c_fill_txfifo(priv, true); + /* + * First chunk of data. For a repeated START condition, do not write + * data to the TX fifo here to avoid the timing issue. + */ + if (!repeat) + uniphier_fi2c_fill_txfifo(priv, true); } static void uniphier_fi2c_rx_init(struct uniphier_fi2c_priv *priv, u16 addr) @@ -361,7 +366,7 @@ static int uniphier_fi2c_master_xfer_one(struct i2c_adapter *adap, if (is_read) uniphier_fi2c_rx_init(priv, msg->addr); else - uniphier_fi2c_tx_init(priv, msg->addr); + uniphier_fi2c_tx_init(priv, msg->addr, repeat); dev_dbg(&adap->dev, "start condition\n"); /* -- cgit v1.2.3 From 8469636ab5d8c77645b953746c10fda6983a8830 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 6 Dec 2018 12:55:27 +0900 Subject: i2c: uniphier: fix violation of tLOW requirement for Fast-mode Currently, the clock duty is set as tLOW/tHIGH = 1/1. For Fast-mode, tLOW is set to 1.25 us while the I2C spec requires tLOW >= 1.3 us. tLOW/tHIGH = 5/4 would meet both Standard-mode and Fast-mode: Standard-mode: tLOW = 5.56 us, tHIGH = 4.44 us Fast-mode: tLOW = 1.39 us, tHIGH = 1.11 us Signed-off-by: Masahiro Yamada Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-uniphier.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-uniphier.c b/drivers/i2c/busses/i2c-uniphier.c index 454f914ae66d..c488e558aef7 100644 --- a/drivers/i2c/busses/i2c-uniphier.c +++ b/drivers/i2c/busses/i2c-uniphier.c @@ -320,7 +320,13 @@ static void uniphier_i2c_hw_init(struct uniphier_i2c_priv *priv) uniphier_i2c_reset(priv, true); - writel((cyc / 2 << 16) | cyc, priv->membase + UNIPHIER_I2C_CLK); + /* + * Bit30-16: clock cycles of tLOW. + * Standard-mode: tLOW = 4.7 us, tHIGH = 4.0 us + * Fast-mode: tLOW = 1.3 us, tHIGH = 0.6 us + * "tLow/tHIGH = 5/4" meets both. + */ + writel((cyc * 5 / 9 << 16) | cyc, priv->membase + UNIPHIER_I2C_CLK); uniphier_i2c_reset(priv, false); } -- cgit v1.2.3 From ece27a337d42a3197935711997f2880f0957ed7e Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 6 Dec 2018 12:55:28 +0900 Subject: i2c: uniphier-f: fix violation of tLOW requirement for Fast-mode Currently, the clock duty is set as tLOW/tHIGH = 1/1. For Fast-mode, tLOW is set to 1.25 us while the I2C spec requires tLOW >= 1.3 us. tLOW/tHIGH = 5/4 would meet both Standard-mode and Fast-mode: Standard-mode: tLOW = 5.56 us, tHIGH = 4.44 us Fast-mode: tLOW = 1.39 us, tHIGH = 1.11 us Signed-off-by: Masahiro Yamada Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-uniphier-f.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c index d8a5db14da79..03da4a539a2f 100644 --- a/drivers/i2c/busses/i2c-uniphier-f.c +++ b/drivers/i2c/busses/i2c-uniphier-f.c @@ -518,9 +518,26 @@ static void uniphier_fi2c_hw_init(struct uniphier_fi2c_priv *priv) uniphier_fi2c_reset(priv); + /* + * Standard-mode: tLOW + tHIGH = 10 us + * Fast-mode: tLOW + tHIGH = 2.5 us + */ writel(cyc, priv->membase + UNIPHIER_FI2C_CYC); - writel(cyc / 2, priv->membase + UNIPHIER_FI2C_LCTL); + /* + * Standard-mode: tLOW = 4.7 us, tHIGH = 4.0 us, tBUF = 4.7 us + * Fast-mode: tLOW = 1.3 us, tHIGH = 0.6 us, tBUF = 1.3 us + * "tLow/tHIGH = 5/4" meets both. + */ + writel(cyc * 5 / 9, priv->membase + UNIPHIER_FI2C_LCTL); + /* + * Standard-mode: tHD;STA = 4.0 us, tSU;STA = 4.7 us, tSU;STO = 4.0 us + * Fast-mode: tHD;STA = 0.6 us, tSU;STA = 0.6 us, tSU;STO = 0.6 us + */ writel(cyc / 2, priv->membase + UNIPHIER_FI2C_SSUT); + /* + * Standard-mode: tSU;DAT = 250 ns + * Fast-mode: tSU;DAT = 100 ns + */ writel(cyc / 16, priv->membase + UNIPHIER_FI2C_DSUT); uniphier_fi2c_prepare_operation(priv); -- cgit v1.2.3