Hi Moritz,

Thanks for the review.


On 10/28/2016 10:41 AM, Moritz Fischer wrote:
> Hi Joshua,
>
> looks good to me; however, I think since you're adding initial support,
> I'd squash this together with [3/5].
I agree. I didn't want to squash it in before putting it up for review, though.
>
> On Fri, Oct 28, 2016 at 09:56:42AM -0700, Joshua Clayton wrote:
>> The status pin may not show ready in the time described in the
>> Altetera manual. check the value several times before giving up
> s/Altetera/Altera
Thanks. I'll fix this. And it will go away when it gets squashed.
>> For the hardware I am working on, the status pin takes 250 us,
>> 5 times as long as described by Altera.
>>
>> Signed-off-by: Joshua Clayton <stillcompil...@gmail.com>
>> ---
>>  drivers/fpga/cyclone-ps-spi.c | 13 ++++++++-----
>>  1 file changed, 8 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/fpga/cyclone-ps-spi.c b/drivers/fpga/cyclone-ps-spi.c
>> index 4b70d5c..c368223 100644
>> --- a/drivers/fpga/cyclone-ps-spi.c
>> +++ b/drivers/fpga/cyclone-ps-spi.c
>> @@ -20,6 +20,7 @@
>>  
>>  #define FPGA_RESET_TIME             50   /* time in usecs to trigger FPGA 
>> config */
>> -#define FPGA_MIN_DELAY              250  /* min usecs to wait for config 
>> status */
>> +#define FPGA_MIN_DELAY              50   /* min usecs to wait for config 
>> status */
>> +#define FPGA_MAX_DELAY              1000 /* max usecs to wait for config 
>> status */
>>  
>>  struct cyclonespi_conf {
>>      struct gpio_desc *config;
>> @@ -42,6 +43,7 @@ static int cyclonespi_write_init(struct fpga_manager *mgr, 
>> u32 flags,
>>                               const char *buf, size_t count)
>>  {
>>      struct cyclonespi_conf *conf = (struct cyclonespi_conf *)mgr->priv;
>> +    int i;
>>  
>>      if (flags & FPGA_MGR_PARTIAL_RECONFIG) {
>>              dev_err(&mgr->dev, "Partial reconfiguration not supported.\n");
>> @@ -56,13 +58,14 @@ static int cyclonespi_write_init(struct fpga_manager 
>> *mgr, u32 flags,
>>      }
>>  
>>      gpiod_set_value(conf->config, 1);
>> -    usleep_range(FPGA_MIN_DELAY, FPGA_MIN_DELAY + 20);
>> -    if (gpiod_get_value(conf->status) == 0) {
>> -            dev_err(&mgr->dev, "Status pin not ready.\n");
>> -            return -EIO;
>> +    for (i = 0; i < (FPGA_MAX_DELAY / FPGA_MIN_DELAY); i++) {
>> +            usleep_range(FPGA_MIN_DELAY, FPGA_MIN_DELAY + 20);
>> +            if (gpiod_get_value(conf->status))
>> +                    return 0;
>>      }
>>  
>> -    return 0;
>> +    dev_err(&mgr->dev, "Status pin not ready.\n");
>> +    return -EIO;
>>  }
>>  
>>  static void rev_buf(void *buf, size_t len)
>> -- 
>> 2.7.4
>>
> Cheers,
>
> Moritz
Joshua

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