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>
diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c
index baaf5a8..a3685d6 100644
--- a/drivers/mfd/ti_am335x_tscadc.c
+++ b/drivers/mfd/ti_am335x_tscadc.c
@@ -95,7 +95,7 @@
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 @@
}
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 @@
tscadc_writel(tscadc_dev, REG_CTRL,
(restore | CNTRLREG_TSCSSENB));
+ tscadc_writel(tscadc_dev, REG_CLKDIV, tscadc_dev->clk_div);
+
return 0;
}
diff --git a/include/linux/mfd/ti_am335x_tscadc.h b/include/linux/mfd/ti_am335x_tscadc.h
index 4befdb8..7b68a06 100644
--- a/include/linux/mfd/ti_am335x_tscadc.h
+++ b/include/linux/mfd/ti_am335x_tscadc.h
@@ -151,6 +151,7 @@
struct mfd_cell cells[TSCADC_CELLS];
u32 reg_se_cache;
spinlock_t reg_lock;
+ unsigned int clk_div;
/* tsc device */
struct titsc *tsc;