[spi-devel-general] [PATCH 3/3] ep93xx: SPI driver platform support code
H Hartley Sweeten
hartleys at visionengravers.com
Mon Mar 15 15:05:38 EDT 2010
On Monday, March 15, 2010 9:26 AM, Mika Westerberg wrote:
> 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.
>
> Patch depends on the previous patch which adds function ep93xx_chip_revision().
>
> Signed-off-by: Mika Westerberg <mika.westerberg at iki.fi>
Mika,
Some initial comments.
> ---
> arch/arm/mach-ep93xx/clock.c | 21 +++++++++++
> 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, 66 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c
> index 5f80092..1dc22cc 100644
> --- a/arch/arm/mach-ep93xx/clock.c
> +++ b/arch/arm/mach-ep93xx/clock.c
> @@ -100,6 +100,10 @@ static struct clk clk_pwm = {
> .parent = &clk_xtali,
> .rate = EP93XX_EXT_CLK_RATE,
> };
> +static struct clk clk_spi = {
> + .parent = &clk_xtali,
> + .rate = EP93XX_EXT_CLK_RATE / 2,
> +};
Please put the clk_spi before the clk_pwm.
> static struct clk clk_video = {
> .sw_locked = 1,
> @@ -187,6 +191,7 @@ static struct clk_lookup clocks[] = {
> INIT_CK("ep93xx-keypad", NULL, &clk_keypad),
> INIT_CK("ep93xx-fb", NULL, &clk_video),
> INIT_CK(NULL, "pwm_clk", &clk_pwm),
> + INIT_CK(NULL, "spi_clk", &clk_spi),
Ditto.
Also, change the init so we can use dev_id matching.
+ INIT_CLK("ep93xx-spi", NULL, &clk_spi),
> INIT_CK(NULL, "m2p0", &clk_m2p0),
> INIT_CK(NULL, "m2p1", &clk_m2p1),
> INIT_CK(NULL, "m2p2", &clk_m2p2),
> @@ -480,6 +485,22 @@ static int __init ep93xx_clock_init(void)
> clk_p.rate / 1000000);
>
> clkdev_add_table(clocks, ARRAY_SIZE(clocks));
> +
> + /*
> + * EP93xx SSP clock rate was doubled in version E2 and forwards. For
> + * more information see:
> + * http://www.cirrus.com/en/pubs/appNote/AN273REV4.pdf
> + */
> + if (ep93xx_chip_revision() >= EP93XX_CHIP_REV_E2) {
> + struct clk *clk;
> +
> + clk = clk_get(NULL, "spi_clk");
> + if (!IS_ERR(clk)) {
> + clk->rate *= 2;
> + clk_put(clk);
> + }
> + }
> +
Please move this block before the pr_info's.
Also, no need to use clk_get/clk_put. Just do:
+ if (ep93xx_chip_revision() >= EP93XX_CHIP_REV_E2)
+ clk_spi.rate *= 2;
> return 0;
> }
> arch_initcall(ep93xx_clock_init);
> diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c
> index 2e496c9..36a7833 100644
> --- a/arch/arm/mach-ep93xx/core.c
> +++ b/arch/arm/mach-ep93xx/core.c
> @@ -31,6 +31,7 @@
> #include <linux/amba/serial.h>
> #include <linux/i2c.h>
> #include <linux/i2c-gpio.h>
> +#include <linux/clk.h>
Is this include necessary?
>
> #include <mach/hardware.h>
> #include <mach/fb.h>
> @@ -389,6 +390,47 @@ 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 + SZ_4K - 1,
The spi resource is only + 0x18 - 1.
> + .flags = IORESOURCE_MEM,
> + },
> + {
> + .start = IRQ_EP93XX_SSP,
Please add the .end value also:
+ .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 8603837..1f02147 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
> {
> @@ -49,6 +50,7 @@ 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);
> void ep93xx_register_pwm(int pwm0, int pwm1);
> +int ep93xx_register_spi(struct ep93xx_spi_info *info);
Please move this up, above ep93xx_register_i2c, to match how it is in the
core.c file.
> int ep93xx_pwm_acquire_gpio(struct platform_device *pdev);
> void ep93xx_pwm_release_gpio(struct platform_device *pdev);
> void ep93xx_register_keypad(struct ep93xx_keypad_platform_data *data);
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