[PATCH v2] media: st_rc: Handle errors of clk_prepare_enable()

From: Evgeny Novikov
Date: Tue Jun 01 2021 - 08:56:55 EST


Hadle errors of clk_prepare_enable() in st_rc_hardware_init() and its
callers.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Evgeny Novikov <novikov@xxxxxxxxx>
---
v2: Add error loging (Sean Young)
---
drivers/media/rc/st_rc.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/media/rc/st_rc.c b/drivers/media/rc/st_rc.c
index 3237fef5d502..d79d1e3996b2 100644
--- a/drivers/media/rc/st_rc.c
+++ b/drivers/media/rc/st_rc.c
@@ -157,8 +157,9 @@ static irqreturn_t st_rc_rx_interrupt(int irq, void *data)
return IRQ_HANDLED;
}

-static void st_rc_hardware_init(struct st_rc_device *dev)
+static int st_rc_hardware_init(struct st_rc_device *dev)
{
+ int ret;
int baseclock, freqdiff;
unsigned int rx_max_symbol_per = MAX_SYMB_TIME;
unsigned int rx_sampling_freq_div;
@@ -166,7 +167,12 @@ static void st_rc_hardware_init(struct st_rc_device *dev)
/* Enable the IP */
reset_control_deassert(dev->rstc);

- clk_prepare_enable(dev->sys_clock);
+ ret = clk_prepare_enable(dev->sys_clock);
+ if (ret) {
+ dev_err(dev->dev, "Failed to prepare/enable system clock\n");
+ return ret;
+ }
+
baseclock = clk_get_rate(dev->sys_clock);

/* IRB input pins are inverted internally from high to low. */
@@ -184,6 +190,8 @@ static void st_rc_hardware_init(struct st_rc_device *dev)
}

writel(rx_max_symbol_per, dev->rx_base + IRB_MAX_SYM_PERIOD);
+
+ return 0;
}

static int st_rc_remove(struct platform_device *pdev)
@@ -287,7 +295,9 @@ static int st_rc_probe(struct platform_device *pdev)

rc_dev->dev = dev;
platform_set_drvdata(pdev, rc_dev);
- st_rc_hardware_init(rc_dev);
+ ret = st_rc_hardware_init(rc_dev);
+ if (ret)
+ goto err;

rdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
/* rx sampling rate is 10Mhz */
@@ -359,6 +369,7 @@ static int st_rc_suspend(struct device *dev)

static int st_rc_resume(struct device *dev)
{
+ int ret;
struct st_rc_device *rc_dev = dev_get_drvdata(dev);
struct rc_dev *rdev = rc_dev->rdev;

@@ -367,7 +378,10 @@ static int st_rc_resume(struct device *dev)
rc_dev->irq_wake = 0;
} else {
pinctrl_pm_select_default_state(dev);
- st_rc_hardware_init(rc_dev);
+ ret = st_rc_hardware_init(rc_dev);
+ if (ret)
+ return ret;
+
if (rdev->users) {
writel(IRB_RX_INTS, rc_dev->rx_base + IRB_RX_INT_EN);
writel(0x01, rc_dev->rx_base + IRB_RX_EN);
--
2.26.2