[ARM] 4832/2: Support AC97CLK on PXA3xx via the clock API

The AC97 clock rate on PXA3xx is generated with a configurable divider
from sys_pll.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 28 insertions, 2 deletions

diff --git a/arch/arm/mach-pxa/pxa3xx.c b/arch/arm/mach-pxa/pxa3xx.c
index 54c9e8371a21..93f3236b4100 100644
--- a/arch/arm/mach-pxa/pxa3xx.c
+++ b/arch/arm/mach-pxa/pxa3xx.c
@@ -110,6 +110,25 @@ unsigned int pxa3xx_get_memclk_frequency_10khz(void)
 }
 
 /*
+ * Return the current AC97 clock frequency.
+ */
+static unsigned long clk_pxa3xx_ac97_getrate(struct clk *clk)
+{
+        unsigned long rate = 312000000;
+        unsigned long ac97_div;
+
+        ac97_div = AC97_DIV;
+
+        /* This may loose precision for some rates but won't for the
+         * standard 24.576MHz.
+         */
+        rate /= (ac97_div >> 12) & 0x7fff;
+        rate *= (ac97_div & 0xfff);
+
+        return rate;
+}
+
+/*
  * Return the current HSIO bus clock frequency
  */
 static unsigned long clk_pxa3xx_hsio_getrate(struct clk *clk)
@@ -156,6 +175,12 @@ static const struct clkops clk_pxa3xx_hsio_ops = {
         .getrate        = clk_pxa3xx_hsio_getrate,
 };
 
+static const struct clkops clk_pxa3xx_ac97_ops = {
+        .enable         = clk_pxa3xx_cken_enable,
+        .disable        = clk_pxa3xx_cken_disable,
+        .getrate        = clk_pxa3xx_ac97_getrate,
+};
+
 static void clk_pout_enable(struct clk *clk)
 {
         OSCC |= OSCC_PEN;
@@ -197,8 +222,9 @@ static struct clk pxa3xx_clks[] = {
                 .delay          = 70,
         },
 
-        PXA3xx_CK("LCDCLK", LCD,    &clk_pxa3xx_hsio_ops, &pxa_device_fb.dev),
-        PXA3xx_CK("CAMCLK", CAMERA, &clk_pxa3xx_hsio_ops, NULL),
+        PXA3xx_CK("LCDCLK",  LCD,    &clk_pxa3xx_hsio_ops, &pxa_device_fb.dev),
+        PXA3xx_CK("CAMCLK",  CAMERA, &clk_pxa3xx_hsio_ops, NULL),
+        PXA3xx_CK("AC97CLK", AC97,   &clk_pxa3xx_ac97_ops, NULL),
 
         PXA3xx_CKEN("UARTCLK", FFUART, 14857000, 1, &pxa_device_ffuart.dev),
         PXA3xx_CKEN("UARTCLK", BTUART, 14857000, 1, &pxa_device_btuart.dev),