[PATCH V3 02/18] ARM: OMAP2+: Add variable to store number of GPMC waitpins

Jon Hunter jon-hunter at ti.com
Tue Mar 19 00:43:47 EST 2013



On 03/16/2013 03:59 PM, Ezequiel Garcia wrote:
> Hi Jon,
> 
> On Fri, Mar 15, 2013 at 10:21:00AM -0500, Jon Hunter wrote:
>> The GPMC has wait-pin signals that can be assigned to a chip-select
>> to monitor the ready signal of an external device. Add a variable to
>> indicate the total number of wait-pins for a given device. This will
>> allow us to detect if the wait-pin being selected is valid or not.
>>
>> When booting with device-tree read the number of wait-pins from the
>> device-tree blob. When device-tree is not used set the number of
>> wait-pins to 4 which is valid for OMAP2-5 devices. Newer devices
>> that have less wait-pins (such as AM335x) only support booting with
>> device-tree and so hard-coding the wait-pin number when not using
>> device-tree is fine.
>>
>> Signed-off-by: Jon Hunter <jon-hunter at ti.com>
>> ---
>>  arch/arm/mach-omap2/gpmc.c |   16 ++++++++++++++++
>>  1 file changed, 16 insertions(+)
>>
>> diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
>> index ef655d9..88a261c 100644
>> --- a/arch/arm/mach-omap2/gpmc.c
>> +++ b/arch/arm/mach-omap2/gpmc.c
>> @@ -108,6 +108,8 @@
>>  #define	GPMC_HAS_WR_ACCESS		0x1
>>  #define	GPMC_HAS_WR_DATA_MUX_BUS	0x2
>>  
>> +#define GPMC_NR_WAITPINS		4
>> +
>>  /* XXX: Only NAND irq has been considered,currently these are the only ones used
>>   */
>>  #define	GPMC_NR_IRQ		2
>> @@ -153,6 +155,7 @@ static struct resource	gpmc_cs_mem[GPMC_CS_NUM];
>>  static DEFINE_SPINLOCK(gpmc_mem_lock);
>>  /* Define chip-selects as reserved by default until probe completes */
>>  static unsigned int gpmc_cs_map = ((1 << GPMC_CS_NUM) - 1);
>> +static unsigned int gpmc_nr_waitpins;
>>  static struct device *gpmc_dev;
>>  static int gpmc_irq;
>>  static resource_size_t phys_base, mem_size;
>> @@ -1297,6 +1300,13 @@ static int gpmc_probe_dt(struct platform_device *pdev)
>>  	if (!of_id)
>>  		return 0;
>>  
>> +	ret = of_property_read_u32(pdev->dev.of_node, "gpmc,num-waitpins",
>> +				   &gpmc_nr_waitpins);
>> +	if (ret < 0) {
>> +		pr_err("%s: number of wait pins not found!\n", __func__);
>> +		return ret;
>> +	}
>> +
>>  	for_each_node_by_name(child, "nand") {
>>  		ret = gpmc_probe_nand_child(pdev, child);
>>  		if (ret < 0) {
>> @@ -1372,6 +1382,12 @@ static int gpmc_probe(struct platform_device *pdev)
>>  	if (gpmc_setup_irq() < 0)
>>  		dev_warn(gpmc_dev, "gpmc_setup_irq failed\n");
>>  
>> +	/* Now the GPMC is initialised, unreserve the chip-selects */
>> +	gpmc_cs_map = 0;
> 
> The above seems to be a remanent of another patch.
> I think you already sent that one, right?

Good catch. I will fix this up.

Jon



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