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spi: Extract spi_toggle_csgpiod() helper for better maintanance

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The multi-CS support splits the comment and the code in the spi_set_cs().
To avoid this in the future extract spi_toggle_csgpiod() helper.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240415193340.1279360-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Andy Shevchenko
2024-04-15 22:31:19 +03:00
committed by Mark Brown
parent df3431fd37
commit e81582c080
1 changed files with 25 additions and 24 deletions
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49
drivers/spi/spi.c
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@@ -1036,6 +1036,29 @@ static inline bool spi_is_last_cs(struct spi_device *spi)
return last;
}
static void spi_toggle_csgpiod(struct spi_device *spi, u8 idx, bool enable, bool activate)
{
/*
* Historically ACPI has no means of the GPIO polarity and
* thus the SPISerialBus() resource defines it on the per-chip
* basis. In order to avoid a chain of negations, the GPIO
* polarity is considered being Active High. Even for the cases
* when _DSD() is involved (in the updated versions of ACPI)
* the GPIO CS polarity must be defined Active High to avoid
* ambiguity. That's why we use enable, that takes SPI_CS_HIGH
* into account.
*/
if (has_acpi_companion(&spi->dev))
gpiod_set_value_cansleep(spi_get_csgpiod(spi, idx), !enable);
else
/* Polarity handled by GPIO library */
gpiod_set_value_cansleep(spi_get_csgpiod(spi, idx), activate);
if (activate)
spi_delay_exec(&spi->cs_setup, NULL);
else
spi_delay_exec(&spi->cs_inactive, NULL);
}
static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
{
@@ -1072,31 +1095,9 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
if (spi_is_csgpiod(spi)) {
if (!(spi->mode & SPI_NO_CS)) {
/*
* Historically ACPI has no means of the GPIO polarity and
* thus the SPISerialBus() resource defines it on the per-chip
* basis. In order to avoid a chain of negations, the GPIO
* polarity is considered being Active High. Even for the cases
* when _DSD() is involved (in the updated versions of ACPI)
* the GPIO CS polarity must be defined Active High to avoid
* ambiguity. That's why we use enable, that takes SPI_CS_HIGH
* into account.
*/
for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) {
if ((spi->cs_index_mask & BIT(idx)) && spi_get_csgpiod(spi, idx)) {
if (has_acpi_companion(&spi->dev))
gpiod_set_value_cansleep(spi_get_csgpiod(spi, idx),
!enable);
else
/* Polarity handled by GPIO library */
gpiod_set_value_cansleep(spi_get_csgpiod(spi, idx),
activate);
if (activate)
spi_delay_exec(&spi->cs_setup, NULL);
else
spi_delay_exec(&spi->cs_inactive, NULL);
}
if ((spi->cs_index_mask & BIT(idx)) && spi_get_csgpiod(spi, idx))
spi_toggle_csgpiod(spi, idx, enable, activate);
}
}
/* Some SPI masters need both GPIO CS & slave_select */