[PATCH v3 2/2] ep93xx: SPI driver platform support code
Mika Westerberg
mika.westerberg at iki.fi
Tue Apr 13 10:10:14 EDT 2010
This patch adds platform side support code for EP93xx SPI driver. This includes
clock, resources and muxing. There is a new function: ep93xx_register_spi() that
can be used by board support code to register new SPI devices for the board.
This patch depends on following ARM patch:
5998/1 ep93xx: added chip revision reading function
Signed-off-by: Mika Westerberg <mika.westerberg at iki.fi>
---
arch/arm/mach-ep93xx/clock.c | 14 +++++++
arch/arm/mach-ep93xx/core.c | 42 +++++++++++++++++++++++
arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h | 1 +
arch/arm/mach-ep93xx/include/mach/platform.h | 2 +
4 files changed, 59 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c
index 5f80092..daaa799 100644
--- a/arch/arm/mach-ep93xx/clock.c
+++ b/arch/arm/mach-ep93xx/clock.c
@@ -96,6 +96,10 @@ static struct clk clk_keypad = {
.enable_mask = EP93XX_SYSCON_KEYTCHCLKDIV_KEN,
.set_rate = set_keytchclk_rate,
};
+static struct clk clk_spi = {
+ .parent = &clk_xtali,
+ .rate = EP93XX_EXT_CLK_RATE / 2,
+};
static struct clk clk_pwm = {
.parent = &clk_xtali,
.rate = EP93XX_EXT_CLK_RATE,
@@ -186,6 +190,7 @@ 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-spi", NULL, &clk_spi),
INIT_CK(NULL, "pwm_clk", &clk_pwm),
INIT_CK(NULL, "m2p0", &clk_m2p0),
INIT_CK(NULL, "m2p1", &clk_m2p1),
@@ -473,6 +478,14 @@ static int __init ep93xx_clock_init(void)
/* Initialize the pll2 derived clocks */
clk_usb_host.rate = clk_pll2.rate / (((value >> 28) & 0xf) + 1);
+ /*
+ * EP93xx SSP clock rate was doubled in version E2. For more information
+ * see:
+ * http://www.cirrus.com/en/pubs/appNote/AN273REV4.pdf
+ */
+ if (ep93xx_chip_revision() >= EP93XX_CHIP_REV_E2)
+ clk_spi.rate *= 2;
+
pr_info("PLL1 running at %ld MHz, PLL2 at %ld MHz\n",
clk_pll1.rate / 1000000, clk_pll2.rate / 1000000);
pr_info("FCLK %ld MHz, HCLK %ld MHz, PCLK %ld MHz\n",
@@ -480,6 +493,7 @@ static int __init ep93xx_clock_init(void)
clk_p.rate / 1000000);
clkdev_add_table(clocks, ARRAY_SIZE(clocks));
+
return 0;
}
arch_initcall(ep93xx_clock_init);
diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c
index 90fb591..08b7747 100644
--- a/arch/arm/mach-ep93xx/core.c
+++ b/arch/arm/mach-ep93xx/core.c
@@ -363,6 +363,48 @@ void __init ep93xx_register_eth(struct ep93xx_eth_data *data, int copy_addr)
platform_device_register(&ep93xx_eth_device);
}
+static struct resource ep93xx_spi_resources[] = {
+ {
+ .start = EP93XX_SPI_PHYS_BASE,
+ .end = EP93XX_SPI_PHYS_BASE + 0x18 - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ {
+ .start = IRQ_EP93XX_SSP,
+ .end = IRQ_EP93XX_SSP,
+ .flags = IORESOURCE_IRQ,
+ },
+};
+
+static struct platform_device ep93xx_spi_device = {
+ .name = "ep93xx-spi",
+ .id = -1,
+ .num_resources = ARRAY_SIZE(ep93xx_spi_resources),
+ .resource = ep93xx_spi_resources,
+};
+
+/**
+ * ep93xx_register_spi() - registers spi platform device
+ * @info: ep93xx board specific spi info
+ *
+ * This function registers platform device for the EP93xx SPI controller and
+ * also makes sure that SPI pins are muxed so that I2S is not using those
+ * pins. Caller should allocate necessary GPIO lines and register any SPI
+ * devices before calling this (see also spi_register_board_info()).
+ *
+ * Returns %0 in success and negative value in case of failure.
+ */
+int __init ep93xx_register_spi(struct ep93xx_spi_info *info)
+{
+ /*
+ * When SPI is used, we need to make sure that I2S is muxed off from
+ * SPI pins.
+ */
+ ep93xx_devcfg_clear_bits(EP93XX_SYSCON_DEVCFG_I2SONSSP);
+
+ ep93xx_spi_device.dev.platform_data = info;
+ return platform_device_register(&ep93xx_spi_device);
+}
/*************************************************************************
* EP93xx i2c peripheral handling
diff --git a/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h b/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
index 93e2ecc..b1e096f 100644
--- a/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
+++ b/arch/arm/mach-ep93xx/include/mach/ep93xx-regs.h
@@ -106,6 +106,7 @@
#define EP93XX_AAC_BASE EP93XX_APB_IOMEM(0x00080000)
+#define EP93XX_SPI_PHYS_BASE EP93XX_APB_PHYS(0x000a0000)
#define EP93XX_SPI_BASE EP93XX_APB_IOMEM(0x000a0000)
#define EP93XX_IRDA_BASE EP93XX_APB_IOMEM(0x000b0000)
diff --git a/arch/arm/mach-ep93xx/include/mach/platform.h b/arch/arm/mach-ep93xx/include/mach/platform.h
index c6dc14d..5816581 100644
--- a/arch/arm/mach-ep93xx/include/mach/platform.h
+++ b/arch/arm/mach-ep93xx/include/mach/platform.h
@@ -9,6 +9,7 @@ struct i2c_board_info;
struct platform_device;
struct ep93xxfb_mach_info;
struct ep93xx_keypad_platform_data;
+struct ep93xx_spi_info;
struct ep93xx_eth_data
{
@@ -34,6 +35,7 @@ static inline void ep93xx_devcfg_clear_bits(unsigned int bits)
}
void ep93xx_register_eth(struct ep93xx_eth_data *data, int copy_addr);
+int ep93xx_register_spi(struct ep93xx_spi_info *info);
void ep93xx_register_i2c(struct i2c_gpio_platform_data *data,
struct i2c_board_info *devices, int num);
void ep93xx_register_fb(struct ep93xxfb_mach_info *data);
--
1.5.6.5
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