[PATCH 3/4] iio: adc: xilinx: Check for return values in clk related functions

[manish.narani@xilinx.com (Manish Narani)]

This patch adds check for return values from clock related functions.
This was reported by static code analysis tool.

Signed-off-by: Manish Narani <manish.narani@xilinx.com>
---
 drivers/iio/adc/xilinx-xadc-core.c | 24 ++++++++++++++++++++++--
 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/xilinx-xadc-core.c b/drivers/iio/adc/xilinx-xadc-core.c
index 248cffa..47eb364 100644
--- a/drivers/iio/adc/xilinx-xadc-core.c
+++ b/drivers/iio/adc/xilinx-xadc-core.c
@@ -322,6 +322,7 @@ static irqreturn_t xadc_zynq_interrupt_handler(int irq, void *devid)
 
 #define XADC_ZYNQ_TCK_RATE_MAX 50000000
 #define XADC_ZYNQ_IGAP_DEFAULT 20
+#define XADC_ZYNQ_PCAP_RATE_MAX 200000000
 
 static int xadc_zynq_setup(struct platform_device *pdev,
 	struct iio_dev *indio_dev, int irq)
@@ -332,6 +333,7 @@ static int xadc_zynq_setup(struct platform_device *pdev,
 	unsigned int div;
 	unsigned int igap;
 	unsigned int tck_rate;
+	int ret;
 
 	/* TODO: Figure out how to make igap and tck_rate configurable */
 	igap = XADC_ZYNQ_IGAP_DEFAULT;
@@ -341,6 +343,13 @@ static int xadc_zynq_setup(struct platform_device *pdev,
 
 	pcap_rate = clk_get_rate(xadc->clk);
 
+	if (pcap_rate > XADC_ZYNQ_PCAP_RATE_MAX) {
+		ret = clk_set_rate(xadc->clk,
+				   (unsigned long)XADC_ZYNQ_PCAP_RATE_MAX);
+		if (ret)
+			return ret;
+	}
+
 	if (tck_rate > pcap_rate / 2) {
 		div = 2;
 	} else {
@@ -366,6 +375,12 @@ static int xadc_zynq_setup(struct platform_device *pdev,
 			XADC_ZYNQ_CFG_REDGE | XADC_ZYNQ_CFG_WEDGE |
 			tck_div | XADC_ZYNQ_CFG_IGAP(igap));
 
+	if (pcap_rate > XADC_ZYNQ_PCAP_RATE_MAX) {
+		ret = clk_set_rate(xadc->clk, pcap_rate);
+		if (ret)
+			return ret;
+	}
+
 	return 0;
 }
 
@@ -887,6 +902,9 @@ static int xadc_write_raw(struct iio_dev *indio_dev,
 	unsigned long clk_rate = xadc_get_dclk_rate(xadc);
 	unsigned int div;
 
+	if (!clk_rate)
+		return -EINVAL;
+
 	if (info != IIO_CHAN_INFO_SAMP_FREQ)
 		return -EINVAL;
 
@@ -1239,8 +1257,10 @@ static int xadc_probe(struct platform_device *pdev)
 		goto err_free_irq;
 
 	/* Disable all alarms */
-	xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_ALARM_MASK,
-		XADC_CONF1_ALARM_MASK);
+	ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_ALARM_MASK,
+				  XADC_CONF1_ALARM_MASK);
+	if (ret)
+		goto err_free_irq;
 
 	/* Set thresholds to min/max */
 	for (i = 0; i < 16; i++) {
-- 
2.1.1