Subject: [PATCH v5 04/14] ARM: OMAP2+: gpmc: minimal driver support

From: [email-masked] (Jon Hunter)
Date: Tue, 12 Jun 2012 14:19:22 -0500

On 06/11/2012 09:26 AM, Afzal Mohammed wrote:
> Create a minimal driver out of gpmc code.
> Responsibilities handled by earlier gpmc
> initialization is now achieved in probe.
> 
> Signed-off-by: Afzal Mohammed <[email-masked]>
> ---
>  arch/arm/mach-omap2/gpmc.c |  170 ++++++++++++++++++++++++++++++++------------
>  1 file changed, 123 insertions(+), 47 deletions(-)
> 
> diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
> index 6dbddb9..a91f40f 100644
> --- a/arch/arm/mach-omap2/gpmc.c
> +++ b/arch/arm/mach-omap2/gpmc.c
> @@ -24,6 +24,7 @@
>  #include <linux/io.h>
>  #include <linux/module.h>
>  #include <linux/interrupt.h>
> +#include <linux/platform_device.h>
>  
>  #include <asm/mach-types.h>
>  #include <plat/gpmc.h>
> @@ -31,6 +32,8 @@
>  
>  #include <plat/sdrc.h>
>  
> +#define	DRIVER_NAME		"omap-gpmc"
> +
>  /* GPMC register offsets */
>  #define GPMC_REVISION		0x00
>  #define GPMC_SYSCONFIG		0x10
> @@ -115,6 +118,21 @@ struct omap3_gpmc_regs {
>  	struct gpmc_cs_config cs_context[GPMC_CS_NUM];
>  };
>  
> +struct gpmc_peripheral {
> +	char			*name;
> +	int			id;
> +	void			*pdata;
> +	unsigned		pdata_size;
> +	struct resource		*per_res;
> +	unsigned		per_res_cnt;
> +	struct resource		*gpmc_res;
> +	unsigned		gpmc_res_cnt;
> +	bool			have_waitpin;
> +	bool			waitpin_polarity;
> +	unsigned		waitpin;
> +	struct platform_device	*pdev;
> +};
> +
>  static struct gpmc_client_irq gpmc_client_irq[GPMC_NR_IRQ];
>  static struct irq_chip gpmc_irq_chip;
>  static unsigned gpmc_irq_start;
> @@ -124,6 +142,10 @@ static struct resource	gpmc_cs_mem[GPMC_CS_NUM];
>  static DEFINE_SPINLOCK(gpmc_mem_lock);
>  static unsigned int gpmc_cs_map;	/* flag for cs which are initialized */
>  static int gpmc_ecc_used = -EINVAL;	/* cs using ecc engine */
> +static struct device *gpmc_dev;
> +static u32 gpmc_revision;
> +static int gpmc_irq;
> +static resource_size_t phys_base, mem_size;
>  
>  static void __iomem *gpmc_base;
>  
> @@ -433,6 +455,19 @@ static int gpmc_cs_insert_mem(int cs, unsigned long base, unsigned long size)
>  	return r;
>  }
>  
> +static int gpmc_cs_delete_mem(int cs)
> +{
> +	struct resource	*res = &gpmc_cs_mem[cs];
> +	int r;
> +
> +	spin_lock(&gpmc_mem_lock);
> +	r = release_resource(&gpmc_cs_mem[cs]);
> +	res->start = res->end = 0;
> +	spin_unlock(&gpmc_mem_lock);
> +
> +	return r;
> +}
> +
>  int gpmc_cs_request(int cs, unsigned long size, unsigned long *base)
>  {
>  	struct resource *res = &gpmc_cs_mem[cs];
> @@ -769,7 +804,7 @@ static void gpmc_irq_noop(struct irq_data *data) { }
>  
>  static unsigned int gpmc_irq_noop_ret(struct irq_data *data) { return 0; }
>  
> -static int gpmc_setup_irq(int gpmc_irq)
> +static int gpmc_setup_irq(void)
>  {
>  	int i;
>  	u32 regval;
> @@ -813,7 +848,37 @@ static int gpmc_setup_irq(int gpmc_irq)
>  	return request_irq(gpmc_irq, gpmc_handle_irq, 0, "gpmc", NULL);
>  }
>  
> -static void __init gpmc_mem_init(void)
> +static __exit int gpmc_free_irq(void)
> +{
> +	int i;
> +
> +	if (gpmc_irq)
> +		free_irq(gpmc_irq, NULL);
> +
> +	for (i = 0; i < GPMC_NR_IRQ; i++) {
> +		irq_set_handler(gpmc_client_irq[i].irq, NULL);
> +		irq_set_chip(gpmc_client_irq[i].irq, &no_irq_chip);
> +		irq_modify_status(gpmc_client_irq[i].irq, 0, 0);
> +	}
> +
> +	irq_free_descs(gpmc_irq_start, GPMC_NR_IRQ);
> +
> +	return 0;
> +}
> +
> +static void __devexit gpmc_mem_exit(void)
> +{
> +	int cs;
> +
> +	for (cs = 0; cs < GPMC_CS_NUM; cs++) {
> +		if (!gpmc_cs_mem_enabled(cs))
> +			continue;
> +		gpmc_cs_delete_mem(cs);
> +	}
> +
> +}
> +
> +static void __devinit gpmc_mem_init(void)
>  {
>  	int cs;
>  	unsigned long boot_rom_space = 0;
> @@ -840,64 +905,75 @@ static void __init gpmc_mem_init(void)
>  	}
>  }
>  
> -static int __init gpmc_init(void)
> +static __devinit int gpmc_probe(struct platform_device *pdev)
>  {
>  	u32 l;
> -	int ret = -EINVAL;
> -	int gpmc_irq;
> -	char *ck = NULL;
> -
> -	if (cpu_is_omap24xx()) {
> -		ck = "core_l3_ck";
> -		if (cpu_is_omap2420())
> -			l = OMAP2420_GPMC_BASE;
> -		else
> -			l = OMAP34XX_GPMC_BASE;
> -		gpmc_irq = INT_34XX_GPMC_IRQ;
> -	} else if (cpu_is_omap34xx()) {
> -		ck = "gpmc_fck";
> -		l = OMAP34XX_GPMC_BASE;
> -		gpmc_irq = INT_34XX_GPMC_IRQ;
> -	} else if (cpu_is_omap44xx()) {
> -		ck = "gpmc_ck";
> -		l = OMAP44XX_GPMC_BASE;
> -		gpmc_irq = OMAP44XX_IRQ_GPMC;
> -	}
> +	struct resource *res;
>  
> -	if (WARN_ON(!ck))
> -		return ret;
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (res == NULL)
> +		return -ENOENT;
>  
> -	gpmc_l3_clk = clk_get(NULL, ck);
> -	if (IS_ERR(gpmc_l3_clk)) {
> -		printk(KERN_ERR "Could not get GPMC clock %s\n", ck);
> -		BUG();
> -	}
> +	phys_base = res->start;
> +	mem_size = resource_size(res);
>  
> -	gpmc_base = ioremap(l, SZ_4K);
> -	if (!gpmc_base) {
> -		clk_put(gpmc_l3_clk);
> -		printk(KERN_ERR "Could not get GPMC register memory\n");
> -		BUG();
> -	}
> +	gpmc_base = devm_request_and_ioremap(&pdev->dev, res);
> +	if (!gpmc_base)
> +		return -EADDRNOTAVAIL;
> +
> +	gpmc_dev = &pdev->dev;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
> +	if (res == NULL)
> +		dev_warn(gpmc_dev, "Failed to get resource: irq\n");
> +	else
> +		gpmc_irq = res->start;
>  
>  	clk_enable(gpmc_l3_clk);

We should be able to get rid of the clk_enable() here and use ...

	pm_runtime_enable(&pdev->dev);
	pm_runtime_get(&pdev->dev);

The clk_disable should also be replaced with a pm_runtime_put(). You
will also need to include pm_runtime.h.

Jon