EP93xx: Add i2s core support

Add core support for EP93xx i2s audio

Signed-off-by: Ryan Mallon <ryan@bluewatersys.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

4 files changed, 146 insertions, 1 deletions

diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c
index 5f80092b6ace..e782af18ffb7 100644
--- a/arch/arm/mach-ep93xx/clock.c
+++ b/arch/arm/mach-ep93xx/clock.c
@@ -43,7 +43,8 @@ static unsigned long get_uart_rate(struct clk *clk);
 
 static int set_keytchclk_rate(struct clk *clk, unsigned long rate);
 static int set_div_rate(struct clk *clk, unsigned long rate);
-
+static int set_i2s_sclk_rate(struct clk *clk, unsigned long rate);
+static int set_i2s_lrclk_rate(struct clk *clk, unsigned long rate);
 
 static struct clk clk_xtali = {
         .rate           = EP93XX_EXT_CLK_RATE,
@@ -108,6 +109,29 @@ static struct clk clk_video = {
         .set_rate       = set_div_rate,
 };
 
+static struct clk clk_i2s_mclk = {
+        .sw_locked      = 1,
+        .enable_reg     = EP93XX_SYSCON_I2SCLKDIV,
+        .enable_mask    = EP93XX_SYSCON_CLKDIV_ENABLE,
+        .set_rate       = set_div_rate,
+};
+
+static struct clk clk_i2s_sclk = {
+        .sw_locked      = 1,
+        .parent         = &clk_i2s_mclk,
+        .enable_reg     = EP93XX_SYSCON_I2SCLKDIV,
+        .enable_mask    = EP93XX_SYSCON_I2SCLKDIV_SENA,
+        .set_rate       = set_i2s_sclk_rate,
+};
+
+static struct clk clk_i2s_lrclk = {
+        .sw_locked      = 1,
+        .parent         = &clk_i2s_sclk,
+        .enable_reg     = EP93XX_SYSCON_I2SCLKDIV,
+        .enable_mask    = EP93XX_SYSCON_I2SCLKDIV_SENA,
+        .set_rate       = set_i2s_lrclk_rate,
+};
+
 /* DMA Clocks */
 static struct clk clk_m2p0 = {
         .parent         = &clk_h,
@@ -186,6 +210,9 @@ static struct clk_lookup clocks[] = {
         INIT_CK("ep93xx-ohci",          NULL,           &clk_usb_host),
         INIT_CK("ep93xx-keypad",        NULL,           &clk_keypad),
         INIT_CK("ep93xx-fb",            NULL,           &clk_video),
+        INIT_CK("ep93xx-i2s",           "mclk",         &clk_i2s_mclk),
+        INIT_CK("ep93xx-i2s",           "sclk",         &clk_i2s_sclk),
+        INIT_CK("ep93xx-i2s",           "lrclk",        &clk_i2s_lrclk),
         INIT_CK(NULL,                   "pwm_clk",      &clk_pwm),
         INIT_CK(NULL,                   "m2p0",         &clk_m2p0),
         INIT_CK(NULL,                   "m2p1",         &clk_m2p1),
@@ -396,6 +423,44 @@ static int set_div_rate(struct clk *clk, unsigned long rate)
         return 0;
 }
 
+static int set_i2s_sclk_rate(struct clk *clk, unsigned long rate)
+{
+        unsigned val = __raw_readl(clk->enable_reg);
+
+        if (rate == clk_i2s_mclk.rate / 2)
+                ep93xx_syscon_swlocked_write(val & ~EP93XX_I2SCLKDIV_SDIV, 
+                                             clk->enable_reg);
+        else if (rate == clk_i2s_mclk.rate / 4)
+                ep93xx_syscon_swlocked_write(val | EP93XX_I2SCLKDIV_SDIV, 
+                                             clk->enable_reg);
+        else
+                return -EINVAL;
+
+        clk_i2s_sclk.rate = rate;
+        return 0;
+}
+
+static int set_i2s_lrclk_rate(struct clk *clk, unsigned long rate)
+{
+        unsigned val = __raw_readl(clk->enable_reg) & 
+                ~EP93XX_I2SCLKDIV_LRDIV_MASK;
+        
+        if (rate == clk_i2s_sclk.rate / 32)
+                ep93xx_syscon_swlocked_write(val | EP93XX_I2SCLKDIV_LRDIV32,
+                                             clk->enable_reg);
+        else if (rate == clk_i2s_sclk.rate / 64)
+                ep93xx_syscon_swlocked_write(val | EP93XX_I2SCLKDIV_LRDIV64,
+                                             clk->enable_reg);
+        else if (rate == clk_i2s_sclk.rate / 128)
+                ep93xx_syscon_swlocked_write(val | EP93XX_I2SCLKDIV_LRDIV128,
+                                             clk->enable_reg);
+        else
+                return -EINVAL;
+
+        clk_i2s_lrclk.rate = rate;
+        return 0;
+}
+
 int clk_set_rate(struct clk *clk, unsigned long rate)
 {
         if (clk->set_rate)
diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c
index 90fb591cbffa..005af0fba334 100644
--- a/arch/arm/mach-ep93xx/core.c
+++ b/arch/arm/mach-ep93xx/core.c
@@ -617,6 +617,73 @@ void ep93xx_keypad_release_gpio(struct platform_device *pdev)
 }
 EXPORT_SYMBOL(ep93xx_keypad_release_gpio);
 
+/*************************************************************************
+ * EP93xx I2S audio peripheral handling
+ *************************************************************************/
+static struct resource ep93xx_i2s_resource[] = {
+        {
+                .start  = EP93XX_I2S_PHYS_BASE,
+                .end    = EP93XX_I2S_PHYS_BASE + 0x100 - 1,
+                .flags  = IORESOURCE_MEM,
+        },
+};
+
+static struct platform_device ep93xx_i2s_device = {
+        .name           = "ep93xx-i2s",
+        .id             = -1,
+        .num_resources  = ARRAY_SIZE(ep93xx_i2s_resource),
+        .resource       = ep93xx_i2s_resource,
+};
+
+void __init ep93xx_register_i2s(void)
+{
+        platform_device_register(&ep93xx_i2s_device);
+}
+
+#define EP93XX_SYSCON_DEVCFG_I2S_MASK   (EP93XX_SYSCON_DEVCFG_I2SONSSP | \
+                                         EP93XX_SYSCON_DEVCFG_I2SONAC97)
+
+#define EP93XX_I2SCLKDIV_MASK           (EP93XX_SYSCON_I2SCLKDIV_ORIDE | \
+                                         EP93XX_SYSCON_I2SCLKDIV_SPOL)
+
+int ep93xx_i2s_acquire(unsigned i2s_pins, unsigned i2s_config)
+{
+        unsigned val;
+
+        /* Sanity check */
+        if (i2s_pins & ~EP93XX_SYSCON_DEVCFG_I2S_MASK)
+                return -EINVAL;
+        if (i2s_config & ~EP93XX_I2SCLKDIV_MASK)
+                return -EINVAL;
+
+        /* Must have only one of I2SONSSP/I2SONAC97 set */
+        if ((i2s_pins & EP93XX_SYSCON_DEVCFG_I2SONSSP) ==
+            (i2s_pins & EP93XX_SYSCON_DEVCFG_I2SONAC97))
+                return -EINVAL;
+
+        ep93xx_devcfg_clear_bits(EP93XX_SYSCON_DEVCFG_I2S_MASK);
+        ep93xx_devcfg_set_bits(i2s_pins);
+
+        /*
+         * This is potentially racy with the clock api for i2s_mclk, sclk and 
+         * lrclk. Since the i2s driver is the only user of those clocks we
+         * rely on it to prevent parallel use of this function and the 
+         * clock api for the i2s clocks.
+         */
+        val = __raw_readl(EP93XX_SYSCON_I2SCLKDIV);
+        val &= ~EP93XX_I2SCLKDIV_MASK;
+        val |= i2s_config;
+        ep93xx_syscon_swlocked_write(val, EP93XX_SYSCON_I2SCLKDIV);
+
+        return 0;
+}
+EXPORT_SYMBOL(ep93xx_i2s_acquire);
+
+void ep93xx_i2s_release(void)
+{
+        ep93xx_devcfg_clear_bits(EP93XX_SYSCON_DEVCFG_I2S_MASK);
+}
+EXPORT_SYMBOL(ep93xx_i2s_release);
 
 extern void ep93xx_gpio_init(void);
 
diff --git a/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h b/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
index 93e2ecc79ceb..3fbb095be6e9 100644
--- a/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
+++ b/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
@@ -93,6 +93,7 @@
 /* APB peripherals */
 #define EP93XX_TIMER_BASE               EP93XX_APB_IOMEM(0x00010000)
 
+#define EP93XX_I2S_PHYS_BASE            EP93XX_APB_PHYS(0x00020000)
 #define EP93XX_I2S_BASE                 EP93XX_APB_IOMEM(0x00020000)
 
 #define EP93XX_SECURITY_BASE            EP93XX_APB_IOMEM(0x00030000)
@@ -193,6 +194,15 @@
 #define EP93XX_SYSCON_CLKDIV_ESEL       (1<<14)
 #define EP93XX_SYSCON_CLKDIV_PSEL       (1<<13)
 #define EP93XX_SYSCON_CLKDIV_PDIV_SHIFT 8
+#define EP93XX_SYSCON_I2SCLKDIV         EP93XX_SYSCON_REG(0x8c)
+#define EP93XX_SYSCON_I2SCLKDIV_SENA    (1<<31)
+#define EP93XX_SYSCON_I2SCLKDIV_ORIDE   (1<<29)
+#define EP93XX_SYSCON_I2SCLKDIV_SPOL    (1<<19)
+#define EP93XX_I2SCLKDIV_SDIV           (1 << 16)
+#define EP93XX_I2SCLKDIV_LRDIV32        (0 << 17)
+#define EP93XX_I2SCLKDIV_LRDIV64        (1 << 17)
+#define EP93XX_I2SCLKDIV_LRDIV128       (2 << 17)
+#define EP93XX_I2SCLKDIV_LRDIV_MASK     (3 << 17)
 #define EP93XX_SYSCON_KEYTCHCLKDIV      EP93XX_SYSCON_REG(0x90)
 #define EP93XX_SYSCON_KEYTCHCLKDIV_TSEN (1<<31)
 #define EP93XX_SYSCON_KEYTCHCLKDIV_ADIV (1<<16)
diff --git a/arch/arm/mach-ep93xx/include/mach/platform.h b/arch/arm/mach-ep93xx/include/mach/platform.h
index c6dc14dbca18..0f2822d7ec8b 100644
--- a/arch/arm/mach-ep93xx/include/mach/platform.h
+++ b/arch/arm/mach-ep93xx/include/mach/platform.h
@@ -43,6 +43,9 @@ void ep93xx_pwm_release_gpio(struct platform_device *pdev);
 void ep93xx_register_keypad(struct ep93xx_keypad_platform_data *data);
 int ep93xx_keypad_acquire_gpio(struct platform_device *pdev);
 void ep93xx_keypad_release_gpio(struct platform_device *pdev);
+void ep93xx_register_i2s(void);
+int ep93xx_i2s_acquire(unsigned i2s_pins, unsigned i2s_config);
+void ep93xx_i2s_release(void);
 
 void ep93xx_init_devices(void);
 extern struct sys_timer ep93xx_timer;