Exynos5250 has external PLL (XusbXTI) for USB 3.0 PHY's
ref_pad_clk. So use this clock based on availability of
gpio to power control this PLL, otherwise use internal
clock only from XXTI.
Signed-off-by: Vivek Gautam <gautam.vivek@xxxxxxxxxxx>
---
drivers/usb/phy/samsung-usb3phy.c | 14 ++++++++++----
drivers/usb/phy/samsung-usbphy.c | 26 ++++++++++++++++++++++++++
drivers/usb/phy/samsung-usbphy.h | 1 +
3 files changed, 37 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/phy/samsung-usb3phy.c b/drivers/usb/phy/samsung-usb3phy.c
index 46dd97c..16b024e 100644
--- a/drivers/usb/phy/samsung-usb3phy.c
+++ b/drivers/usb/phy/samsung-usb3phy.c
@@ -24,6 +24,7 @@
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
+#include <linux/gpio.h>
#include <linux/pm_runtime.h>
#include <linux/usb/samsung_usb_phy.h>
#include <linux/platform_data/samsung-usbphy.h>
@@ -224,12 +225,17 @@ static int samsung_exynos5_usb3phy_init(struct usb_phy *phy, bool use_ext_clk)
*/
static int samsung_usb3phy_init(struct usb_phy *phy)
{
+ struct samsung_usbphy *sphy = phy_to_sphy(phy);
+
/*
- * We start with using PHY refclk from external PLL,
- * once runtime suspend for the device is called this
- * will change to internal core clock
+ * We check if we have a PHY ref_clk gpio available, then only
+ * use XusbXTI (external PLL); otherwise use internal core clock
+ * from XXTI.
*/
- return samsung_exynos5_usb3phy_init(phy, true);
+ if (gpio_is_valid(sphy->phyclk_gpio))
+ return samsung_exynos5_usb3phy_init(phy, true);
+ else
+ return samsung_exynos5_usb3phy_init(phy, false);
}
/*
diff --git a/drivers/usb/phy/samsung-usbphy.c b/drivers/usb/phy/samsung-usbphy.c
index ab4fa11..6968d12 100644
--- a/drivers/usb/phy/samsung-usbphy.c
+++ b/drivers/usb/phy/samsung-usbphy.c
@@ -27,6 +27,7 @@
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
+#include <linux/of_gpio.h>
#include <linux/usb/samsung_usb_phy.h>
#include "samsung-usbphy.h"
@@ -34,6 +35,7 @@
int samsung_usbphy_parse_dt(struct samsung_usbphy *sphy)
{
struct device_node *usbphy_sys;
+ int ret;
/* Getting node for system controller interface for usb-phy */
usbphy_sys = of_get_child_by_name(sphy->dev->of_node, "usbphy-sys");
@@ -58,6 +60,30 @@ int samsung_usbphy_parse_dt(struct samsung_usbphy *sphy)
if (sphy->sysreg == NULL)
dev_warn(sphy->dev, "Can't get usb-phy sysreg cfg register\n");
+ /* Getting PHY clk gpio here to enable/disable PHY clock PLL, if any */
+ sphy->phyclk_gpio = of_get_named_gpio(sphy->dev->of_node,
+ "samsung,phyclk-gpio", 0);
+ /*
+ * We don't want to return error code here in case we don't get the
+ * PHY clock gpio, some PHYs may not have it.
+ */
+ if (gpio_is_valid(sphy->phyclk_gpio)) {
+ ret = gpio_request_one(sphy->phyclk_gpio, GPIOF_INIT_HIGH,
+ "samsung_usb_phy_clock_en");
+ if (ret) {
+ /*
+ * We don't want to return error code here,
+ * sometimes either of usb2 phy or usb3 phy may not
+ * have the PHY clock gpio.
+ */
+ dev_err(sphy->dev, "can't request phyclk gpio %d\n",
+ sphy->phyclk_gpio);
+ sphy->phyclk_gpio = -EINVAL;
+ }
+ } else {
+ dev_warn(sphy->dev, "Can't get usb-phy clock gpio\n");
+ }
+
of_node_put(usbphy_sys);
return 0;
diff --git a/drivers/usb/phy/samsung-usbphy.h b/drivers/usb/phy/samsung-usbphy.h
index f7e657d..1921ab0 100644
--- a/drivers/usb/phy/samsung-usbphy.h
+++ b/drivers/usb/phy/samsung-usbphy.h
@@ -300,6 +300,7 @@ struct samsung_usbphy {
enum samsung_usb_phy_type phy_type;
atomic_t phy_usage;
spinlock_t lock;
+ int phyclk_gpio;
};
#define phy_to_sphy(x) container_of((x), struct samsung_usbphy, phy)
--
1.7.6.5
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
