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

[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.nar...@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