The AT91 PMC (Power Management Controller) provides a USB clock used by
the different USB controllers (ehci, ohci and udc).
The atmel-ehci driver must configure the usb clock rate to 48Mhz in order
to get a fully functionnal USB host controller.
This configuration was formely done in mach-at91/clock.c, but will be
bypassed when moving to common clk framework.
This patch adds support for usb clock retrieval and configuration only if
CCF is enabled (CONFIG_COMMON_CLK).
Signed-off-by: Boris BREZILLON <b.brezillon@xxxxxxxxxxx>
---
drivers/usb/host/ehci-atmel.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/host/ehci-atmel.c b/drivers/usb/host/ehci-atmel.c
index 3b645ff..f417526 100644
--- a/drivers/usb/host/ehci-atmel.c
+++ b/drivers/usb/host/ehci-atmel.c
@@ -30,13 +30,17 @@ static const char hcd_name[] = "ehci-atmel";
static struct hc_driver __read_mostly ehci_atmel_hc_driver;
/* interface and function clocks */
-static struct clk *iclk, *fclk;
+static struct clk *iclk, *fclk, *uclk;
static int clocked;
/*-------------------------------------------------------------------------*/
static void atmel_start_clock(void)
{
+ if (IS_ENABLED(CONFIG_COMMON_CLK)) {
+ clk_set_rate(uclk, 48000000);
+ clk_prepare_enable(uclk);
+ }
clk_prepare_enable(iclk);
clk_prepare_enable(fclk);
clocked = 1;
@@ -46,6 +50,8 @@ static void atmel_stop_clock(void)
{
clk_disable_unprepare(fclk);
clk_disable_unprepare(iclk);
+ if (IS_ENABLED(CONFIG_COMMON_CLK))
+ clk_disable_unprepare(uclk);
clocked = 0;
}
@@ -130,6 +136,14 @@ static int ehci_atmel_drv_probe(struct platform_device *pdev)
retval = -ENOENT;
goto fail_request_resource;
}
+ if (IS_ENABLED(CONFIG_COMMON_CLK)) {
+ uclk = devm_clk_get(&pdev->dev, "usb_clk");
+ if (IS_ERR(uclk)) {
+ dev_err(&pdev->dev, "failed to get uclk\n");
+ retval = PTR_ERR(uclk);
+ goto fail_request_resource;
+ }
+ }
ehci = hcd_to_ehci(hcd);
/* registers start at offset 0x0 */
--
1.7.9.5
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