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path: root/drivers/i2c/busses/i2c-imx.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-imx.c')
-rw-r--r--drivers/i2c/busses/i2c-imx.c108
1 files changed, 86 insertions, 22 deletions
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index f751d231ded8..ee0d25b498cb 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -335,6 +335,7 @@ static const struct of_device_id i2c_imx_dt_ids[] = {
{ .compatible = "fsl,imx6sll-i2c", .data = &imx6_i2c_hwdata, },
{ .compatible = "fsl,imx6sx-i2c", .data = &imx6_i2c_hwdata, },
{ .compatible = "fsl,imx6ul-i2c", .data = &imx6_i2c_hwdata, },
+ { .compatible = "fsl,imx7d-i2c", .data = &imx6_i2c_hwdata, },
{ .compatible = "fsl,imx7s-i2c", .data = &imx6_i2c_hwdata, },
{ .compatible = "fsl,imx8mm-i2c", .data = &imx6_i2c_hwdata, },
{ .compatible = "fsl,imx8mn-i2c", .data = &imx6_i2c_hwdata, },
@@ -396,17 +397,16 @@ static void i2c_imx_reset_regs(struct imx_i2c_struct *i2c_imx)
}
/* Functions for DMA support */
-static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
- dma_addr_t phy_addr)
+static int i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx, dma_addr_t phy_addr)
{
struct imx_i2c_dma *dma;
struct dma_slave_config dma_sconfig;
- struct device *dev = &i2c_imx->adapter.dev;
+ struct device *dev = i2c_imx->adapter.dev.parent;
int ret;
dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
if (!dma)
- return;
+ return -ENOMEM;
dma->chan_tx = dma_request_chan(dev, "tx");
if (IS_ERR(dma->chan_tx)) {
@@ -451,7 +451,7 @@ static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n",
dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx));
- return;
+ return 0;
fail_rx:
dma_release_channel(dma->chan_rx);
@@ -459,6 +459,8 @@ fail_tx:
dma_release_channel(dma->chan_tx);
fail_al:
devm_kfree(dev, dma);
+
+ return ret;
}
static void i2c_imx_dma_callback(void *arg)
@@ -532,22 +534,20 @@ static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx)
static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool atomic)
{
+ bool multi_master = i2c_imx->multi_master;
unsigned long orig_jiffies = jiffies;
unsigned int temp;
- if (!i2c_imx->multi_master)
- return 0;
-
while (1) {
temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
/* check for arbitration lost */
- if (temp & I2SR_IAL) {
+ if (multi_master && (temp & I2SR_IAL)) {
i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
return -EAGAIN;
}
- if (for_busy && (temp & I2SR_IBB)) {
+ if (for_busy && (!multi_master || (temp & I2SR_IBB))) {
i2c_imx->stopped = 0;
break;
}
@@ -622,8 +622,8 @@ static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
return 0;
}
-static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
- unsigned int i2c_clk_rate)
+static int i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
+ unsigned int i2c_clk_rate)
{
struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->hwdata->clk_div;
unsigned int div;
@@ -638,7 +638,11 @@ static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
/* Divider value calculation */
if (i2c_imx->cur_clk == i2c_clk_rate)
- return;
+ return 0;
+
+ /* Keep the denominator of the following program always NOT equal to 0. */
+ if (!(i2c_clk_rate / 2))
+ return -EINVAL;
i2c_imx->cur_clk = i2c_clk_rate;
@@ -669,6 +673,8 @@ static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
dev_dbg(&i2c_imx->adapter.dev, "IFDR[IC]=0x%x, REAL DIV=%d\n",
i2c_clk_div[i].val, i2c_clk_div[i].div);
#endif
+
+ return 0;
}
static int i2c_imx_clk_notifier_call(struct notifier_block *nb,
@@ -678,11 +684,12 @@ static int i2c_imx_clk_notifier_call(struct notifier_block *nb,
struct imx_i2c_struct *i2c_imx = container_of(nb,
struct imx_i2c_struct,
clk_change_nb);
+ int ret = 0;
if (action & POST_RATE_CHANGE)
- i2c_imx_set_clk(i2c_imx, ndata->new_rate);
+ ret = i2c_imx_set_clk(i2c_imx, ndata->new_rate);
- return NOTIFY_OK;
+ return notifier_from_errno(ret);
}
static int i2c_imx_start(struct imx_i2c_struct *i2c_imx, bool atomic)
@@ -1761,7 +1768,8 @@ static int i2c_imx_probe(struct platform_device *pdev)
goto rpm_disable;
/* Request IRQ */
- ret = request_irq(irq, i2c_imx_isr, IRQF_SHARED, pdev->name, i2c_imx);
+ ret = request_irq(irq, i2c_imx_isr, IRQF_SHARED | IRQF_NO_SUSPEND,
+ pdev->name, i2c_imx);
if (ret) {
dev_err(&pdev->dev, "can't claim irq %d\n", irq);
goto rpm_disable;
@@ -1781,7 +1789,11 @@ static int i2c_imx_probe(struct platform_device *pdev)
i2c_imx->bitrate = pdata->bitrate;
i2c_imx->clk_change_nb.notifier_call = i2c_imx_clk_notifier_call;
clk_notifier_register(i2c_imx->clk, &i2c_imx->clk_change_nb);
- i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk));
+ ret = i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk));
+ if (ret < 0) {
+ dev_err(&pdev->dev, "can't get I2C clock\n");
+ goto clk_notifier_unregister;
+ }
i2c_imx_reset_regs(i2c_imx);
@@ -1791,6 +1803,22 @@ static int i2c_imx_probe(struct platform_device *pdev)
if (ret == -EPROBE_DEFER)
goto clk_notifier_unregister;
+ /*
+ * DMA mode should be optional for I2C, when encountering DMA errors,
+ * no need to exit I2C probe. Only print warning to show DMA error and
+ * use PIO mode directly to ensure I2C bus available as much as possible.
+ */
+ ret = i2c_imx_dma_request(i2c_imx, phy_addr);
+ if (ret) {
+ if (ret == -EPROBE_DEFER)
+ goto clk_notifier_unregister;
+ else if (ret == -ENODEV)
+ dev_dbg(&pdev->dev, "Only use PIO mode\n");
+ else
+ dev_warn(&pdev->dev, "Failed to setup DMA (%pe), only use PIO mode\n",
+ ERR_PTR(ret));
+ }
+
/* Add I2C adapter */
ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
if (ret < 0)
@@ -1805,9 +1833,6 @@ static int i2c_imx_probe(struct platform_device *pdev)
i2c_imx->adapter.name);
dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
- /* Init DMA config if supported */
- i2c_imx_dma_request(i2c_imx, phy_addr);
-
return 0; /* Return OK */
clk_notifier_unregister:
@@ -1859,8 +1884,7 @@ static int i2c_imx_runtime_suspend(struct device *dev)
struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev);
clk_disable(i2c_imx->clk);
-
- return 0;
+ return pinctrl_pm_select_sleep_state(dev);
}
static int i2c_imx_runtime_resume(struct device *dev)
@@ -1868,6 +1892,10 @@ static int i2c_imx_runtime_resume(struct device *dev)
struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev);
int ret;
+ ret = pinctrl_pm_select_default_state(dev);
+ if (ret)
+ return ret;
+
ret = clk_enable(i2c_imx->clk);
if (ret)
dev_err(dev, "can't enable I2C clock, ret=%d\n", ret);
@@ -1875,7 +1903,43 @@ static int i2c_imx_runtime_resume(struct device *dev)
return ret;
}
+static int i2c_imx_suspend(struct device *dev)
+{
+ /*
+ * Some I2C devices may need the I2C controller to remain active
+ * during resume_noirq() or suspend_noirq(). If the controller is
+ * autosuspended, there is no way to wake it up once runtime PM is
+ * disabled (in suspend_late()).
+ *
+ * During system resume, the I2C controller will be available only
+ * after runtime PM is re-enabled (in resume_early()). However, this
+ * may be too late for some devices.
+ *
+ * Wake up the controller in the suspend() callback while runtime PM
+ * is still enabled. The I2C controller will remain available until
+ * the suspend_noirq() callback (pm_runtime_force_suspend()) is
+ * called. During resume, the I2C controller can be restored by the
+ * resume_noirq() callback (pm_runtime_force_resume()).
+ *
+ * Finally, the resume() callback re-enables autosuspend, ensuring
+ * the I2C controller remains available until the system enters
+ * suspend_noirq() and from resume_noirq().
+ */
+ return pm_runtime_resume_and_get(dev);
+}
+
+static int i2c_imx_resume(struct device *dev)
+{
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+ return 0;
+}
+
static const struct dev_pm_ops i2c_imx_pm_ops = {
+ NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SYSTEM_SLEEP_PM_OPS(i2c_imx_suspend, i2c_imx_resume)
RUNTIME_PM_OPS(i2c_imx_runtime_suspend, i2c_imx_runtime_resume, NULL)
};
generated by cgit v1.2.3 (git 2.39.0) at 2025-08-05 22:01:58 +0300