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authorMarek Szyprowski <m.szyprowski@samsung.com>2014-05-07 07:04:14 (GMT)
committerMarek Szyprowski <m.szyprowski@samsung.com>2014-05-15 05:29:29 (GMT)
commit36de3d9a1a856a88f3c7f98d4a3a2ec0fd2cd407 (patch)
treeb77c94bb575003f3d291d6fc7117e8eccf6c36fa
parente4d1633d11272feadb2ba6494618e75660dc0cef (diff)
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usb: usb5303: add support for reference clock specified in device tree
USB3503 chip supports 8 values of reference clock. The value is specified by REF_SEL[1:0] pins and INT_N line. This patch add support for getting 'refclk' clock, enabling it and setting INT_N line according to the value of the gathered clock. If no clock has been specified, driver defaults to the old behaviour (assuming that clock has been specified by REF_SEL pins from primary reference clock frequencies table). Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Change-Id: I3453e714f9a793640b8cb6c0b4ccf699661ec934
-rw-r--r--drivers/usb/misc/usb3503.c28
1 files changed, 26 insertions, 2 deletions
diff --git a/drivers/usb/misc/usb3503.c b/drivers/usb/misc/usb3503.c
index a31641e..52cb754 100644
--- a/drivers/usb/misc/usb3503.c
+++ b/drivers/usb/misc/usb3503.c
@@ -18,6 +18,7 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
+#include <linux/clk.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/delay.h>
@@ -57,10 +58,12 @@ struct usb3503 {
enum usb3503_mode mode;
struct regmap *regmap;
struct device *dev;
+ struct clk *clk;
u8 port_off_mask;
int gpio_intn;
int gpio_reset;
int gpio_connect;
+ bool secondary_ref_clk;
};
static int usb3503_reset(struct usb3503 *hub, int state)
@@ -186,6 +189,25 @@ static int usb3503_probe(struct usb3503 *hub)
} else if (np) {
hub->port_off_mask = 0;
+ hub->clk = devm_clk_get(dev, "refclk");
+ if (!IS_ERR(hub->clk)) {
+ unsigned long rate;
+
+ clk_prepare_enable(hub->clk);
+ rate = clk_get_rate(hub->clk);
+
+ if (rate == 38400000 || rate == 26000000 ||
+ rate == 19200000 || rate == 12000000)
+ hub->secondary_ref_clk = 0;
+ else if (rate == 24000000 || rate == 27000000 ||
+ rate == 25000000 || rate == 50000000)
+ hub->secondary_ref_clk = 1;
+ else
+ dev_err(dev,
+ "unsupported reference clock rate (%d)\n",
+ rate);
+ }
+
property = of_get_property(np, "disabled-ports", &len);
if (property && (len / sizeof(u32)) > 0) {
int i;
@@ -213,8 +235,10 @@ static int usb3503_probe(struct usb3503 *hub)
dev_err(dev, "Ports disabled with no control interface\n");
if (gpio_is_valid(hub->gpio_intn)) {
- err = devm_gpio_request_one(dev, hub->gpio_intn,
- GPIOF_OUT_INIT_HIGH, "usb3503 intn");
+ int val = hub->secondary_ref_clk ? GPIOF_OUT_INIT_LOW :
+ GPIOF_OUT_INIT_HIGH;
+ err = devm_gpio_request_one(dev, hub->gpio_intn, val,
+ "usb3503 intn");
if (err) {
dev_err(dev,
"unable to request GPIO %d as connect pin (%d)\n",