[PATCH 3/3] mtd: gpmi: change the code for clocks

Huang Shijie b32955 at freescale.com
Thu Jun 28 22:32:54 EDT 2012


于 2012年06月29日 10:06, Shawn Guo 写道:
> On Thu, Jun 28, 2012 at 11:52:05PM -0400, Huang Shijie wrote:
>> From: Huang Shijie<b32955 at freescale.com>
>>
>> The gpmi nand driver may needs several clocks(MX6Q needs five clocks).
>>
>> In the old clock framework, all these clocks are chained together,
>> all you need is to manipulate the first clock.
>>
>> But the kernel uses the common clk framework now, which forces us to
>> get the clocks one by one. When we use them, we have to enable them
>> one by one too.
>>
>> Signed-off-by: Huang Shijie<b32955 at freescale.com>
>> Signed-off-by: Huang Shijie<shijie8 at gmail.com>
>> ---
>>   drivers/mtd/nand/gpmi-nand/gpmi-lib.c  |   43 ++++++++++++++++++----
>>   drivers/mtd/nand/gpmi-nand/gpmi-nand.c |   63 +++++++++++++++++++++++++++-----
>>   drivers/mtd/nand/gpmi-nand/gpmi-nand.h |    3 +-
>>   3 files changed, 91 insertions(+), 18 deletions(-)
>>
>> diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
>> index a1f4332..c3778c0 100644
>> --- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
>> +++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
>> @@ -124,12 +124,40 @@ error:
>>   	return -ETIMEDOUT;
>>   }
>>
>> +static int __gpmi_enable_clk(struct gpmi_nand_data *this, bool v)
>> +{
>> +	struct clk *clk;
>> +	int ret;
>> +	int i;
>> +
>> +	for (i = 0; i<  GPMI_CLK_MAX; i++) {
>> +		clk = this->resources.clock[i];
>> +		if (!clk)
>> +			break;
>> +
>> +		if (v) {
>> +			ret = clk_prepare_enable(clk);
>> +			if (ret)
>> +				goto err_clk;
>> +		} else {
>> +			clk_disable_unprepare(clk);
>> +		}
>> +	}
>> +	return 0;
>> +
>> +err_clk:
>> +	return ret;
>> +}
>> +
>> +#define gpmi_enable_clk(x) __gpmi_enable_clk(x, true)
>> +#define gpmi_disable_clk(x) __gpmi_enable_clk(x, false)
>> +
>>   int gpmi_init(struct gpmi_nand_data *this)
>>   {
>>   	struct resources *r =&this->resources;
>>   	int ret;
>>
>> -	ret = clk_prepare_enable(r->clock);
>> +	ret = gpmi_enable_clk(this);
>>   	if (ret)
>>   		goto err_out;
>>   	ret = gpmi_reset_block(r->gpmi_regs, false);
>> @@ -149,7 +177,7 @@ int gpmi_init(struct gpmi_nand_data *this)
>>   	/* Select BCH ECC. */
>>   	writel(BM_GPMI_CTRL1_BCH_MODE, r->gpmi_regs + HW_GPMI_CTRL1_SET);
>>
>> -	clk_disable_unprepare(r->clock);
>> +	gpmi_disable_clk(this);
>>   	return 0;
>>   err_out:
>>   	return ret;
>> @@ -205,7 +233,7 @@ int bch_set_geometry(struct gpmi_nand_data *this)
>>   	ecc_strength  = bch_geo->ecc_strength>>  1;
>>   	page_size     = bch_geo->page_size;
>>
>> -	ret = clk_prepare_enable(r->clock);
>> +	ret = gpmi_enable_clk(this);
>>   	if (ret)
>>   		goto err_out;
>>
>> @@ -240,7 +268,7 @@ int bch_set_geometry(struct gpmi_nand_data *this)
>>   	writel(BM_BCH_CTRL_COMPLETE_IRQ_EN,
>>   				r->bch_regs + HW_BCH_CTRL_SET);
>>
>> -	clk_disable_unprepare(r->clock);
>> +	gpmi_disable_clk(this);
>>   	return 0;
>>   err_out:
>>   	return ret;
>> @@ -716,7 +744,7 @@ void gpmi_begin(struct gpmi_nand_data *this)
>>   	int ret;
>>
>>   	/* Enable the clock. */
>> -	ret = clk_prepare_enable(r->clock);
>> +	ret = gpmi_enable_clk(this);
>>   	if (ret) {
>>   		pr_err("We failed in enable the clk\n");
>>   		goto err_out;
>> @@ -727,7 +755,7 @@ void gpmi_begin(struct gpmi_nand_data *this)
>>   		gpmi_regs + HW_GPMI_TIMING1);
>>
>>   	/* Get the timing information we need. */
>> -	nfc->clock_frequency_in_hz = clk_get_rate(r->clock);
>> +	nfc->clock_frequency_in_hz = clk_get_rate(r->clock[0]);
>>   	clock_period_in_ns = 1000000000 / nfc->clock_frequency_in_hz;
>>
>>   	gpmi_nfc_compute_hardware_timing(this,&hw);
>> @@ -784,8 +812,7 @@ err_out:
>>
>>   void gpmi_end(struct gpmi_nand_data *this)
>>   {
>> -	struct resources *r =&this->resources;
>> -	clk_disable_unprepare(r->clock);
>> +	gpmi_disable_clk(this);
>>   }
>>
>>   /* Clears a BCH interrupt. */
>> diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
>> index 941cfb7..edda3b1 100644
>> --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
>> +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
>> @@ -464,9 +464,59 @@ acquire_err:
>>   	return -EINVAL;
>>   }
>>
>> +static void gpmi_put_clks(struct gpmi_nand_data *this)
>> +{
>> +	struct resources *r =&this->resources;
>> +	struct clk *clk;
>> +	int i;
>> +
>> +	for (i = 0; i<  GPMI_CLK_MAX; i++) {
>> +		clk = r->clock[i];
>> +		if (clk) {
>> +			clk_put(clk);
>> +			r->clock[i] = NULL;
>> +		}
>> +	}
>> +}
>> +
>> +static char *extra_clks_for_mx6q[] = {
>> +	"gpmi_apb", "gpmi_bch", "gpmi_bch_apb", "per1_bch",
>> +};
>> +
>> +static int __devinit gpmi_get_clks(struct gpmi_nand_data *this)
>> +{
>> +	struct resources *r =&this->resources;
>> +	char **extra_clks = NULL;
>> +	struct clk *clk;
>> +	int i;
>> +
>> +	r->clock[0] = clk_get(&this->pdev->dev, NULL);
>> +	if (IS_ERR(r->clock[0]))
>> +		goto err_clock;
>> +
>> +	/* Get extra clocks */
>> +	if (GPMI_IS_MX6Q(this))
>> +		extra_clks = extra_clks_for_mx6q;
> We probably do not need this tweaking.  We can have the driver always
> take all those 5 clocks, and I think the current imx28 clock driver
> can just work with it, because the gpmi-nand clkdev lookup has NULL
> con_id and all those 5 clocks can match the same one on imx28.
>
thanks. got it.


Best Regards
Huang Shijie
>> +	if (!extra_clks)
>> +		return 0;
>> +
>> +	for (i = 1; i<  GPMI_CLK_MAX; i++) {
>> +		clk = clk_get(NULL, extra_clks[i - 1]);
> You should not put NULL but&this->pdev->dev here.
>
> Regards,
> Shawn
>
>> +		if (IS_ERR(clk))
>> +			goto err_clock;
>> +
>> +		r->clock[i] = clk;
>> +	}
>> +	return 0;
>> +
>> +err_clock:
>> +	pr_err("failed in finding the clocks.\n");
>> +	gpmi_put_clks(this);
>> +	return -ENOMEM;
>> +}
>> +
>>   static int __devinit acquire_resources(struct gpmi_nand_data *this)
>>   {
>> -	struct resources *res =&this->resources;
>>   	struct pinctrl *pinctrl;
>>   	int ret;
>>
>> @@ -492,12 +542,9 @@ static int __devinit acquire_resources(struct gpmi_nand_data *this)
>>   		goto exit_pin;
>>   	}
>>
>> -	res->clock = clk_get(&this->pdev->dev, NULL);
>> -	if (IS_ERR(res->clock)) {
>> -		pr_err("can not get the clock\n");
>> -		ret = -ENOENT;
>> +	ret = gpmi_get_clks(this);
>> +	if (ret)
>>   		goto exit_clock;
>> -	}
>>   	return 0;
>>
>>   exit_clock:
>> @@ -512,9 +559,7 @@ exit_regs:
>>
>>   static void release_resources(struct gpmi_nand_data *this)
>>   {
>> -	struct resources *r =&this->resources;
>> -
>> -	clk_put(r->clock);
>> +	gpmi_put_clks(this);
>>   	release_register_block(this);
>>   	release_bch_irq(this);
>>   	release_dma_channels(this);
>> diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.h b/drivers/mtd/nand/gpmi-nand/gpmi-nand.h
>> index ce5daa1..1547a60 100644
>> --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.h
>> +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.h
>> @@ -22,6 +22,7 @@
>>   #include<linux/dma-mapping.h>
>>   #include<linux/fsl/mxs-dma.h>
>>
>> +#define GPMI_CLK_MAX 5 /* MX6Q needs five clocks */
>>   struct resources {
>>   	void          *gpmi_regs;
>>   	void          *bch_regs;
>> @@ -29,7 +30,7 @@ struct resources {
>>   	unsigned int  bch_high_interrupt;
>>   	unsigned int  dma_low_channel;
>>   	unsigned int  dma_high_channel;
>> -	struct clk    *clock;
>> +	struct clk    *clock[GPMI_CLK_MAX];
>>   };
>>
>>   /**
>> -- 
>> 1.7.4.4
>>





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