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author | Boris BREZILLON <b.brezillon@overkiz.com> | 2013-10-18 21:26:51 +0200 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-10-30 09:41:49 -0700 |
commit | 0d768fcfc01098ae0e676c78746c9f4fd8228cd7 (patch) | |
tree | dc952daa17af977f0436513459ff31f4e548bc51 /drivers/usb | |
parent | 9983d6dc4e8a8a1ce599cb426c0ec9384219b476 (diff) | |
download | blackbird-op-linux-0d768fcfc01098ae0e676c78746c9f4fd8228cd7.tar.gz blackbird-op-linux-0d768fcfc01098ae0e676c78746c9f4fd8228cd7.zip |
USB: ehci-atmel: add usb_clk for transition to CCF
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@overkiz.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
-rw-r--r-- | drivers/usb/host/ehci-atmel.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/drivers/usb/host/ehci-atmel.c b/drivers/usb/host/ehci-atmel.c index 3b645ff46f7b..f417526fb1f4 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 */ |