mfd: ti_am335x_tscadc: Restore clock divider on resume

The ADC clock divider needs to be restored on resume as the register content
is lost when the ADC is powered down

Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c
index baaf5a8123bb..a3685d6ef674 100644
--- a/drivers/mfd/ti_am335x_tscadc.c
+++ b/drivers/mfd/ti_am335x_tscadc.c
@@ -95,7 +95,7 @@ static	int ti_tscadc_probe(struct platform_device *pdev)
         const __be32            *cur;
         u32                     val;
         int                     err, ctrl;
-        int                     clk_value, clock_rate;
+        int                     clock_rate;
         int                     tsc_wires = 0, adc_channels = 0, total_channels;
         int                     readouts = 0;
 
@@ -196,11 +196,11 @@ static	int ti_tscadc_probe(struct platform_device *pdev)
         }
         clock_rate = clk_get_rate(clk);
         clk_put(clk);
-        clk_value = clock_rate / ADC_CLK;
+        tscadc->clk_div = clock_rate / ADC_CLK;
 
         /* TSCADC_CLKDIV needs to be configured to the value minus 1 */
-        clk_value = clk_value - 1;
-        tscadc_writel(tscadc, REG_CLKDIV, clk_value);
+        tscadc->clk_div--;
+        tscadc_writel(tscadc, REG_CLKDIV, tscadc->clk_div);
 
         /* Set the control register bits */
         ctrl = CNTRLREG_STEPCONFIGWRT |
@@ -303,6 +303,8 @@ static int tscadc_resume(struct device *dev)
         tscadc_writel(tscadc_dev, REG_CTRL,
                         (restore | CNTRLREG_TSCSSENB));
 
+        tscadc_writel(tscadc_dev, REG_CLKDIV, tscadc_dev->clk_div);
+
         return 0;
 }