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| author | Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> | 2022-07-28 11:21:50 +0530 |
|---|---|---|
| committer | Wolfram Sang <wsa@kernel.org> | 2022-09-27 22:31:52 +0200 |
| commit | 58b924241d0a23eee8e86dd9e6f5dacd01c82e62 (patch) | |
| tree | c4fa4a308c634e6962e2a134a9970ee99f7b559a /drivers/i2c | |
| parent | bdc4af281b70b7fe2881fd08f1aa1b15f2b6adf0 (diff) | |
| download | linux-58b924241d0a23eee8e86dd9e6f5dacd01c82e62.tar.gz linux-58b924241d0a23eee8e86dd9e6f5dacd01c82e62.tar.bz2 linux-58b924241d0a23eee8e86dd9e6f5dacd01c82e62.zip | |
i2c: cadence: Add standard bus recovery support
Hook up the standard GPIO/pinctrl-based recovery support.
We are doing the recovery at the beginning on a timeout.
Multiple people have contributed to the series.
Original patch from Cirag and another one from Robert.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Acked-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-cadence.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c index 33f5588a50c0..fe0cd205502d 100644 --- a/drivers/i2c/busses/i2c-cadence.c +++ b/drivers/i2c/busses/i2c-cadence.c @@ -10,10 +10,12 @@ #include <linux/i2c.h> #include <linux/interrupt.h> #include <linux/io.h> +#include <linux/iopoll.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/of.h> #include <linux/pm_runtime.h> +#include <linux/pinctrl/consumer.h> /* Register offsets for the I2C device. */ #define CDNS_I2C_CR_OFFSET 0x00 /* Control Register, RW */ @@ -127,6 +129,8 @@ #define CDNS_I2C_TIMEOUT_MAX 0xFF #define CDNS_I2C_BROKEN_HOLD_BIT BIT(0) +#define CDNS_I2C_POLL_US 100000 +#define CDNS_I2C_TIMEOUT_US 500000 #define cdns_i2c_readreg(offset) readl_relaxed(id->membase + offset) #define cdns_i2c_writereg(val, offset) writel_relaxed(val, id->membase + offset) @@ -204,6 +208,7 @@ struct cdns_i2c { struct notifier_block clk_rate_change_nb; u32 quirks; u32 ctrl_reg; + struct i2c_bus_recovery_info rinfo; #if IS_ENABLED(CONFIG_I2C_SLAVE) u16 ctrl_reg_diva_divb; struct i2c_client *slave; @@ -840,8 +845,14 @@ static int cdns_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, #endif /* Check if the bus is free */ - if (cdns_i2c_readreg(CDNS_I2C_SR_OFFSET) & CDNS_I2C_SR_BA) { + + ret = readl_relaxed_poll_timeout(id->membase + CDNS_I2C_SR_OFFSET, + reg, + !(reg & CDNS_I2C_SR_BA), + CDNS_I2C_POLL_US, CDNS_I2C_TIMEOUT_US); + if (ret) { ret = -EAGAIN; + i2c_recover_bus(adap); goto out; } @@ -1250,6 +1261,12 @@ static int cdns_i2c_probe(struct platform_device *pdev) id->quirks = data->quirks; } + id->rinfo.pinctrl = devm_pinctrl_get(&pdev->dev); + if (IS_ERR(id->rinfo.pinctrl)) { + dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n"); + return PTR_ERR(id->rinfo.pinctrl); + } + id->membase = devm_platform_get_and_ioremap_resource(pdev, 0, &r_mem); if (IS_ERR(id->membase)) return PTR_ERR(id->membase); @@ -1266,6 +1283,7 @@ static int cdns_i2c_probe(struct platform_device *pdev) id->adap.retries = 3; /* Default retry value. */ id->adap.algo_data = id; id->adap.dev.parent = &pdev->dev; + id->adap.bus_recovery_info = &id->rinfo; init_completion(&id->xfer_done); snprintf(id->adap.name, sizeof(id->adap.name), "Cadence I2C at %08lx", (unsigned long)r_mem->start); |