14 Apr
2020
14 Apr
'20
7:57 p.m.
+static struct gpiod_lookup_table pcm512x_gpios_table = {
- /* .dev_id set during probe */
- .table = {
GPIO_LOOKUP("pcm512x-gpio", 3, "PCM512x-GPIO4", GPIO_ACTIVE_HIGH),It says GPIO 4 and here is number 3. Does this 4 come from hardware documentation?
Yes TI count from 1 to 6 in their documentation. The initial HifiBerry DAC+ also counts from 1 to 6. I can add a comment here.
{ },No comma for terminator entries.
ok
- },
+};
...
- gpiod_add_lookup_table(&pcm512x_gpios_table);
Where is the counterpart gpiod_remove_lookup_table() call?
Ah that's a miss, thanks for flagging this. I remember looking but obviously needed a coffee at the time.
- ctx->gpio_4 = devm_gpiod_get(&pdev->dev, "PCM512x-GPIO4",
GPIOD_OUT_LOW);Can driver work without this GPIO? If so, perhaps devm_gpiod_get_optional().
that part yes, it's only for the LED, but if this fails then probably the rest of the code will also fail.
- if (IS_ERR(ctx->gpio_4)) {
dev_err(&pdev->dev, "gpio4 not found\n");ret = PTR_ERR(ctx->gpio_4);return ret;- }