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-rw-r--r--drivers/i2c/busses/i2c-aspeed.c48
-rw-r--r--drivers/i2c/busses/i2c-designware-common.c16
-rw-r--r--drivers/i2c/busses/i2c-ocores.c4
-rw-r--r--drivers/i2c/busses/i2c-pxa.c76
-rw-r--r--drivers/i2c/busses/i2c-qcom-geni.c8
-rw-r--r--drivers/i2c/busses/i2c-rk3x.c13
-rw-r--r--drivers/i2c/i2c-core.h4
7 files changed, 131 insertions, 38 deletions
diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
index 28e2a5fc4528..5511fd46a65e 100644
--- a/drivers/i2c/busses/i2c-aspeed.c
+++ b/drivers/i2c/busses/i2c-aspeed.c
@@ -249,18 +249,46 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
if (!slave)
return 0;
- command = readl(bus->base + ASPEED_I2C_CMD_REG);
+ /*
+ * Handle stop conditions early, prior to SLAVE_MATCH. Some masters may drive
+ * transfers with low enough latency between the nak/stop phase of the current
+ * command and the start/address phase of the following command that the
+ * interrupts are coalesced by the time we process them.
+ */
+ if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) {
+ irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP;
+ bus->slave_state = ASPEED_I2C_SLAVE_STOP;
+ }
+
+ if (irq_status & ASPEED_I2CD_INTR_TX_NAK &&
+ bus->slave_state == ASPEED_I2C_SLAVE_READ_PROCESSED) {
+ irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
+ bus->slave_state = ASPEED_I2C_SLAVE_STOP;
+ }
+
+ /* Propagate any stop conditions to the slave implementation. */
+ if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) {
+ i2c_slave_event(slave, I2C_SLAVE_STOP, &value);
+ bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
+ }
- /* Slave was requested, restart state machine. */
+ /*
+ * Now that we've dealt with any potentially coalesced stop conditions,
+ * address any start conditions.
+ */
if (irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) {
irq_handled |= ASPEED_I2CD_INTR_SLAVE_MATCH;
bus->slave_state = ASPEED_I2C_SLAVE_START;
}
- /* Slave is not currently active, irq was for someone else. */
+ /*
+ * If the slave has been stopped and not started then slave interrupt
+ * handling is complete.
+ */
if (bus->slave_state == ASPEED_I2C_SLAVE_INACTIVE)
return irq_handled;
+ command = readl(bus->base + ASPEED_I2C_CMD_REG);
dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n",
irq_status, command);
@@ -279,17 +307,6 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
irq_handled |= ASPEED_I2CD_INTR_RX_DONE;
}
- /* Slave was asked to stop. */
- if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) {
- irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP;
- bus->slave_state = ASPEED_I2C_SLAVE_STOP;
- }
- if (irq_status & ASPEED_I2CD_INTR_TX_NAK &&
- bus->slave_state == ASPEED_I2C_SLAVE_READ_PROCESSED) {
- irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
- bus->slave_state = ASPEED_I2C_SLAVE_STOP;
- }
-
switch (bus->slave_state) {
case ASPEED_I2C_SLAVE_READ_REQUESTED:
if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_ACK))
@@ -324,8 +341,7 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, &value);
break;
case ASPEED_I2C_SLAVE_STOP:
- i2c_slave_event(slave, I2C_SLAVE_STOP, &value);
- bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
+ /* Stop event handling is done early. Unreachable. */
break;
case ASPEED_I2C_SLAVE_START:
/* Slave was just started. Waiting for the next event. */;
diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index affcfb243f0f..35f762872b8a 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -63,7 +63,7 @@ static int dw_reg_read(void *context, unsigned int reg, unsigned int *val)
{
struct dw_i2c_dev *dev = context;
- *val = readl_relaxed(dev->base + reg);
+ *val = readl(dev->base + reg);
return 0;
}
@@ -72,7 +72,7 @@ static int dw_reg_write(void *context, unsigned int reg, unsigned int val)
{
struct dw_i2c_dev *dev = context;
- writel_relaxed(val, dev->base + reg);
+ writel(val, dev->base + reg);
return 0;
}
@@ -81,7 +81,7 @@ static int dw_reg_read_swab(void *context, unsigned int reg, unsigned int *val)
{
struct dw_i2c_dev *dev = context;
- *val = swab32(readl_relaxed(dev->base + reg));
+ *val = swab32(readl(dev->base + reg));
return 0;
}
@@ -90,7 +90,7 @@ static int dw_reg_write_swab(void *context, unsigned int reg, unsigned int val)
{
struct dw_i2c_dev *dev = context;
- writel_relaxed(swab32(val), dev->base + reg);
+ writel(swab32(val), dev->base + reg);
return 0;
}
@@ -99,8 +99,8 @@ static int dw_reg_read_word(void *context, unsigned int reg, unsigned int *val)
{
struct dw_i2c_dev *dev = context;
- *val = readw_relaxed(dev->base + reg) |
- (readw_relaxed(dev->base + reg + 2) << 16);
+ *val = readw(dev->base + reg) |
+ (readw(dev->base + reg + 2) << 16);
return 0;
}
@@ -109,8 +109,8 @@ static int dw_reg_write_word(void *context, unsigned int reg, unsigned int val)
{
struct dw_i2c_dev *dev = context;
- writew_relaxed(val, dev->base + reg);
- writew_relaxed(val >> 16, dev->base + reg + 2);
+ writew(val, dev->base + reg);
+ writew(val >> 16, dev->base + reg + 2);
return 0;
}
diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
index 041a76f71a49..e106af83cef4 100644
--- a/drivers/i2c/busses/i2c-ocores.c
+++ b/drivers/i2c/busses/i2c-ocores.c
@@ -771,8 +771,8 @@ static int ocores_i2c_resume(struct device *dev)
return ocores_init(dev, i2c);
}
-static DEFINE_SIMPLE_DEV_PM_OPS(ocores_i2c_pm,
- ocores_i2c_suspend, ocores_i2c_resume);
+static DEFINE_NOIRQ_DEV_PM_OPS(ocores_i2c_pm,
+ ocores_i2c_suspend, ocores_i2c_resume);
static struct platform_driver ocores_i2c_driver = {
.probe = ocores_i2c_probe,
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 1d7648242749..76f79b68cef8 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -265,6 +265,9 @@ struct pxa_i2c {
u32 hs_mask;
struct i2c_bus_recovery_info recovery;
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *pinctrl_default;
+ struct pinctrl_state *pinctrl_recovery;
};
#define _IBMR(i2c) ((i2c)->reg_ibmr)
@@ -1299,12 +1302,13 @@ static void i2c_pxa_prepare_recovery(struct i2c_adapter *adap)
*/
gpiod_set_value(i2c->recovery.scl_gpiod, ibmr & IBMR_SCLS);
gpiod_set_value(i2c->recovery.sda_gpiod, ibmr & IBMR_SDAS);
+
+ WARN_ON(pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_recovery));
}
static void i2c_pxa_unprepare_recovery(struct i2c_adapter *adap)
{
struct pxa_i2c *i2c = adap->algo_data;
- struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
u32 isr;
/*
@@ -1318,7 +1322,7 @@ static void i2c_pxa_unprepare_recovery(struct i2c_adapter *adap)
i2c_pxa_do_reset(i2c);
}
- WARN_ON(pinctrl_select_state(bri->pinctrl, bri->pins_default));
+ WARN_ON(pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_default));
dev_dbg(&i2c->adap.dev, "recovery: IBMR 0x%08x ISR 0x%08x\n",
readl(_IBMR(i2c)), readl(_ISR(i2c)));
@@ -1340,20 +1344,76 @@ static int i2c_pxa_init_recovery(struct pxa_i2c *i2c)
if (IS_ENABLED(CONFIG_I2C_PXA_SLAVE))
return 0;
- bri->pinctrl = devm_pinctrl_get(dev);
- if (PTR_ERR(bri->pinctrl) == -ENODEV) {
- bri->pinctrl = NULL;
+ i2c->pinctrl = devm_pinctrl_get(dev);
+ if (PTR_ERR(i2c->pinctrl) == -ENODEV)
+ i2c->pinctrl = NULL;
+ if (IS_ERR(i2c->pinctrl))
+ return PTR_ERR(i2c->pinctrl);
+
+ if (!i2c->pinctrl)
+ return 0;
+
+ i2c->pinctrl_default = pinctrl_lookup_state(i2c->pinctrl,
+ PINCTRL_STATE_DEFAULT);
+ i2c->pinctrl_recovery = pinctrl_lookup_state(i2c->pinctrl, "recovery");
+
+ if (IS_ERR(i2c->pinctrl_default) || IS_ERR(i2c->pinctrl_recovery)) {
+ dev_info(dev, "missing pinmux recovery information: %ld %ld\n",
+ PTR_ERR(i2c->pinctrl_default),
+ PTR_ERR(i2c->pinctrl_recovery));
+ return 0;
+ }
+
+ /*
+ * Claiming GPIOs can influence the pinmux state, and may glitch the
+ * I2C bus. Do this carefully.
+ */
+ bri->scl_gpiod = devm_gpiod_get(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN);
+ if (bri->scl_gpiod == ERR_PTR(-EPROBE_DEFER))
+ return -EPROBE_DEFER;
+ if (IS_ERR(bri->scl_gpiod)) {
+ dev_info(dev, "missing scl gpio recovery information: %pe\n",
+ bri->scl_gpiod);
+ return 0;
+ }
+
+ /*
+ * We have SCL. Pull SCL low and wait a bit so that SDA glitches
+ * have no effect.
+ */
+ gpiod_direction_output(bri->scl_gpiod, 0);
+ udelay(10);
+ bri->sda_gpiod = devm_gpiod_get(dev, "sda", GPIOD_OUT_HIGH_OPEN_DRAIN);
+
+ /* Wait a bit in case of a SDA glitch, and then release SCL. */
+ udelay(10);
+ gpiod_direction_output(bri->scl_gpiod, 1);
+
+ if (bri->sda_gpiod == ERR_PTR(-EPROBE_DEFER))
+ return -EPROBE_DEFER;
+
+ if (IS_ERR(bri->sda_gpiod)) {
+ dev_info(dev, "missing sda gpio recovery information: %pe\n",
+ bri->sda_gpiod);
return 0;
}
- if (IS_ERR(bri->pinctrl))
- return PTR_ERR(bri->pinctrl);
bri->prepare_recovery = i2c_pxa_prepare_recovery;
bri->unprepare_recovery = i2c_pxa_unprepare_recovery;
+ bri->recover_bus = i2c_generic_scl_recovery;
i2c->adap.bus_recovery_info = bri;
- return 0;
+ /*
+ * Claiming GPIOs can change the pinmux state, which confuses the
+ * pinctrl since pinctrl's idea of the current setting is unaffected
+ * by the pinmux change caused by claiming the GPIO. Work around that
+ * by switching pinctrl to the GPIO state here. We do it this way to
+ * avoid glitching the I2C bus.
+ */
+ pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_recovery);
+
+ return pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_default);
}
static int i2c_pxa_probe(struct platform_device *dev)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
index 6d829ed2f868..0d2e7171e3a6 100644
--- a/drivers/i2c/busses/i2c-qcom-geni.c
+++ b/drivers/i2c/busses/i2c-qcom-geni.c
@@ -858,6 +858,7 @@ static int geni_i2c_probe(struct platform_device *pdev)
ret = geni_se_resources_on(&gi2c->se);
if (ret) {
dev_err(dev, "Error turning on resources %d\n", ret);
+ clk_disable_unprepare(gi2c->core_clk);
return ret;
}
proto = geni_se_read_proto(&gi2c->se);
@@ -877,8 +878,11 @@ static int geni_i2c_probe(struct platform_device *pdev)
/* FIFO is disabled, so we can only use GPI DMA */
gi2c->gpi_mode = true;
ret = setup_gpi_dma(gi2c);
- if (ret)
+ if (ret) {
+ geni_se_resources_off(&gi2c->se);
+ clk_disable_unprepare(gi2c->core_clk);
return dev_err_probe(dev, ret, "Failed to setup GPI DMA mode\n");
+ }
dev_dbg(dev, "Using GPI DMA mode for I2C\n");
} else {
@@ -891,6 +895,8 @@ static int geni_i2c_probe(struct platform_device *pdev)
if (!tx_depth) {
dev_err(dev, "Invalid TX FIFO depth\n");
+ geni_se_resources_off(&gi2c->se);
+ clk_disable_unprepare(gi2c->core_clk);
return -EINVAL;
}
diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c
index a044ca0c35a1..4362db7c5789 100644
--- a/drivers/i2c/busses/i2c-rk3x.c
+++ b/drivers/i2c/busses/i2c-rk3x.c
@@ -178,6 +178,7 @@ struct rk3x_i2c_soc_data {
* @clk: function clk for rk3399 or function & Bus clks for others
* @pclk: Bus clk for rk3399
* @clk_rate_nb: i2c clk rate change notify
+ * @irq: irq number
* @t: I2C known timing information
* @lock: spinlock for the i2c bus
* @wait: the waitqueue to wait for i2c transfer
@@ -200,6 +201,7 @@ struct rk3x_i2c {
struct clk *clk;
struct clk *pclk;
struct notifier_block clk_rate_nb;
+ int irq;
/* Settings */
struct i2c_timings t;
@@ -1087,13 +1089,18 @@ static int rk3x_i2c_xfer_common(struct i2c_adapter *adap,
spin_unlock_irqrestore(&i2c->lock, flags);
- rk3x_i2c_start(i2c);
-
if (!polling) {
+ rk3x_i2c_start(i2c);
+
timeout = wait_event_timeout(i2c->wait, !i2c->busy,
msecs_to_jiffies(WAIT_TIMEOUT));
} else {
+ disable_irq(i2c->irq);
+ rk3x_i2c_start(i2c);
+
timeout = rk3x_i2c_wait_xfer_poll(i2c);
+
+ enable_irq(i2c->irq);
}
spin_lock_irqsave(&i2c->lock, flags);
@@ -1310,6 +1317,8 @@ static int rk3x_i2c_probe(struct platform_device *pdev)
return ret;
}
+ i2c->irq = irq;
+
platform_set_drvdata(pdev, i2c);
if (i2c->soc_data->calc_timings == rk3x_i2c_v0_calc_timings) {
diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h
index 05b8b8dfa9bd..36587f38dff3 100644
--- a/drivers/i2c/i2c-core.h
+++ b/drivers/i2c/i2c-core.h
@@ -3,6 +3,7 @@
* i2c-core.h - interfaces internal to the I2C framework
*/
+#include <linux/kconfig.h>
#include <linux/rwsem.h>
struct i2c_devinfo {
@@ -29,7 +30,8 @@ int i2c_dev_irq_from_resources(const struct resource *resources,
*/
static inline bool i2c_in_atomic_xfer_mode(void)
{
- return system_state > SYSTEM_RUNNING && !preemptible();
+ return system_state > SYSTEM_RUNNING &&
+ (IS_ENABLED(CONFIG_PREEMPT_COUNT) ? !preemptible() : irqs_disabled());
}
static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap)
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