[PATCH v1] media: st-rc: Add reset support

From: srinivas.kandagatla
Date: Tue Jan 14 2014 - 06:10:19 EST


From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxx>

Some of the SOCs hold the IRB IP in softreset state by default.
For this IP to work driver needs to bring it out of softreset.
This patch adds support to reset the IP via reset framework.

Without this patch the driver can not work with SoCs which holds the IP
in softreset.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxx>
---
drivers/media/rc/st_rc.c | 13 +++++++++++++
1 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/drivers/media/rc/st_rc.c b/drivers/media/rc/st_rc.c
index 65120c2..8f0cddb 100644
--- a/drivers/media/rc/st_rc.c
+++ b/drivers/media/rc/st_rc.c
@@ -13,6 +13,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
+#include <linux/reset.h>
#include <media/rc-core.h>
#include <linux/pinctrl/consumer.h>

@@ -28,6 +29,7 @@ struct st_rc_device {
int sample_mult;
int sample_div;
bool rxuhfmode;
+ struct reset_control *rstc;
};

/* Registers */
@@ -161,6 +163,10 @@ static void st_rc_hardware_init(struct st_rc_device *dev)
unsigned int rx_max_symbol_per = MAX_SYMB_TIME;
unsigned int rx_sampling_freq_div;

+ /* Enable the IP */
+ if (dev->rstc)
+ reset_control_deassert(dev->rstc);
+
clk_prepare_enable(dev->sys_clock);
baseclock = clk_get_rate(dev->sys_clock);

@@ -271,6 +277,11 @@ static int st_rc_probe(struct platform_device *pdev)
else
rc_dev->rx_base = rc_dev->base;

+
+ rc_dev->rstc = reset_control_get(dev, NULL);
+ if (IS_ERR(rc_dev->rstc))
+ rc_dev->rstc = NULL;
+
rc_dev->dev = dev;
platform_set_drvdata(pdev, rc_dev);
st_rc_hardware_init(rc_dev);
@@ -338,6 +349,8 @@ static int st_rc_suspend(struct device *dev)
writel(0x00, rc_dev->rx_base + IRB_RX_EN);
writel(0x00, rc_dev->rx_base + IRB_RX_INT_EN);
clk_disable_unprepare(rc_dev->sys_clock);
+ if (rc_dev->rstc)
+ reset_control_assert(rc_dev->rstc);
}

return 0;
--
1.7.6.5

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