On Thu, Nov 1, 2018 at 4:22 PM Anatolij Gustschin <agust@xxxxxxx> wrote:
Hi Anatolij,
>
> Driver probing fails on non-dt platforms since of_match_device()
> always returns NULL here. Add device names and matching driver
> data to the spi_device_id table. This allows driver binding to
> dynamically added PS-SPI devices (e.g. added via spi_new_device()
> after hot-plugging).
Need to update the header to explain what has been added since v2
(added spi ids and an array and code to map spi ids to data).
>
> Signed-off-by: Anatolij Gustschin <agust@xxxxxxx>
> ---
> Changes in v3:
> - don't use pointers to device data struct in driver_data
>
> Changes in v2:
> - removed not necessary braces {}
> - dropped not needed !id check
>
> drivers/fpga/altera-ps-spi.c | 36 +++++++++++++++++++++++++++++++-----
> 1 file changed, 31 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/fpga/altera-ps-spi.c b/drivers/fpga/altera-ps-spi.c
> index 33aafda50af5..78d809194b7d 100644
> --- a/drivers/fpga/altera-ps-spi.c
> +++ b/drivers/fpga/altera-ps-spi.c
> @@ -75,6 +75,11 @@ static struct altera_ps_data a10_data = {
> .t_st2ck_us = 10, /* min(t_ST2CK) */
> };
>
> +static const struct altera_ps_data *altera_ps_data_map[] = {
Please add a comment that array index is enum altera_ps_devtype or
something like that. Make it easy for future generations to do the
right thing. :)
> + &c5_data,
> + &a10_data,
> +};
> +
> static const struct of_device_id of_ef_match[] = {
> { .compatible = "altr,fpga-passive-serial", .data = &c5_data },
> { .compatible = "altr,fpga-arria10-passive-serial", .data = &a10_data },
> @@ -234,6 +239,19 @@ static const struct fpga_manager_ops altera_ps_ops = {
> .write_complete = altera_ps_write_complete,
> };
>
> +static const struct altera_ps_data *id_to_data(const struct spi_device_id *id)
> +{
> + const struct altera_ps_data *data;
> + unsigned int i;
> +
> + for (i = 0; i < ARRAY_SIZE(altera_ps_data_map); i++) {
At this point, id->driver_data == CYCLONE5 or ARRIA10 (more added in
the future) so we don't need a loop to search the mapping array for a
matching id. Would something like the following work instead of
this for loop? I understand you wanted to do some checking, this
accomplishes some checking but will exit NULL if someone extends the
array wrongly.
kernel_ulong_t devtype = id->driver_data;
/* someone added a altera_ps_devtype without adding to the map array */
if (devtype >= ARRAY_SIZE(altera_ps_data_map))
return NULL;
data = altera_ps_data_map[devtype];
if (!data || data->devtype != devtype)
return NULL;
return data;
> + data = altera_ps_data_map[i];
> + if (data && data->devtype == id->driver_data)
> + return data;
> + }
> + return NULL;
> +}
> +
> static int altera_ps_probe(struct spi_device *spi)
> {
> struct altera_ps_conf *conf;
> @@ -244,11 +262,17 @@ static int altera_ps_probe(struct spi_device *spi)
> if (!conf)
> return -ENOMEM;
>
> - of_id = of_match_device(of_ef_match, &spi->dev);
> - if (!of_id)
> - return -ENODEV;
> + if (spi->dev.of_node) {
> + of_id = of_match_device(of_ef_match, &spi->dev);
> + if (!of_id)
> + return -ENODEV;
> + conf->data = of_id->data;
> + } else {
> + conf->data = id_to_data(spi_get_device_id(spi));
> + if (!conf->data)
> + return -ENODEV;
> + }
>
> - conf->data = of_id->data;
> conf->spi = spi;
> conf->config = devm_gpiod_get(&spi->dev, "nconfig", GPIOD_OUT_LOW);
> if (IS_ERR(conf->config)) {
> @@ -294,7 +318,9 @@ static int altera_ps_remove(struct spi_device *spi)
> }
>
> static const struct spi_device_id altera_ps_spi_ids[] = {
> - {"cyclone-ps-spi", 0},
> + { "cyclone-ps-spi", CYCLONE5 },
> + { "fpga-passive-serial", CYCLONE5 },
> + { "fpga-arria10-passive-serial", ARRIA10 },
> {}
> };
> MODULE_DEVICE_TABLE(spi, altera_ps_spi_ids);
> --
> 2.17.1
Thanks,
Alan
>
