diff options
| author | Otto Pflüger <otto.pflueger@abscue.de> | 2023-07-24 08:56:53 +0200 |
|---|---|---|
| committer | Noralf Trønnes <noralf@tronnes.org> | 2023-08-02 13:18:07 +0200 |
| commit | 8cc8ccbaa5d89b65a32f0260b0cd2288d2c9b6dc (patch) | |
| tree | 02179c3cc499b92f0aab81412628704415a5c0a3 /drivers/gpu/drm/tiny | |
| parent | 8e4bb53c902ed2b06a2c4778e6dbb2c1eeec4960 (diff) | |
drm/mipi-dbi: Lock SPI bus before setting D/C GPIO
Multiple displays may be connected to the same bus and share a D/C GPIO,
so the display driver needs exclusive access to the bus to ensure that
it can control the D/C GPIO safely.
Signed-off-by: Otto Pflüger <otto.pflueger@abscue.de>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: David Lechner <david@lechnology.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230724065654.5269-2-otto.pflueger@abscue.de
Diffstat (limited to 'drivers/gpu/drm/tiny')
| -rw-r--r-- | drivers/gpu/drm/tiny/ili9225.c | 7 | ||||
| -rw-r--r-- | drivers/gpu/drm/tiny/ili9486.c | 4 |
2 files changed, 10 insertions, 1 deletions
diff --git a/drivers/gpu/drm/tiny/ili9225.c b/drivers/gpu/drm/tiny/ili9225.c index 077c6ff5a2e1..4ceb68ffac4b 100644 --- a/drivers/gpu/drm/tiny/ili9225.c +++ b/drivers/gpu/drm/tiny/ili9225.c @@ -316,19 +316,24 @@ static int ili9225_dbi_command(struct mipi_dbi *dbi, u8 *cmd, u8 *par, u32 speed_hz; int ret; + spi_bus_lock(spi->controller); gpiod_set_value_cansleep(dbi->dc, 0); speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 1); ret = mipi_dbi_spi_transfer(spi, speed_hz, 8, cmd, 1); + spi_bus_unlock(spi->controller); if (ret || !num) return ret; if (*cmd == ILI9225_WRITE_DATA_TO_GRAM && !dbi->swap_bytes) bpw = 16; + spi_bus_lock(spi->controller); gpiod_set_value_cansleep(dbi->dc, 1); speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num); + ret = mipi_dbi_spi_transfer(spi, speed_hz, bpw, par, num); + spi_bus_unlock(spi->controller); - return mipi_dbi_spi_transfer(spi, speed_hz, bpw, par, num); + return ret; } static const struct drm_simple_display_pipe_funcs ili9225_pipe_funcs = { diff --git a/drivers/gpu/drm/tiny/ili9486.c b/drivers/gpu/drm/tiny/ili9486.c index 02265c898816..938bceed5999 100644 --- a/drivers/gpu/drm/tiny/ili9486.c +++ b/drivers/gpu/drm/tiny/ili9486.c @@ -59,9 +59,11 @@ static int waveshare_command(struct mipi_dbi *mipi, u8 *cmd, u8 *par, * before being transferred as 8-bit on the big endian SPI bus. */ buf[0] = cpu_to_be16(*cmd); + spi_bus_lock(spi->controller); gpiod_set_value_cansleep(mipi->dc, 0); speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 2); ret = mipi_dbi_spi_transfer(spi, speed_hz, 8, buf, 2); + spi_bus_unlock(spi->controller); if (ret || !num) goto free; @@ -79,9 +81,11 @@ static int waveshare_command(struct mipi_dbi *mipi, u8 *cmd, u8 *par, if (*cmd == MIPI_DCS_WRITE_MEMORY_START && !mipi->swap_bytes) bpw = 16; + spi_bus_lock(spi->controller); gpiod_set_value_cansleep(mipi->dc, 1); speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num); ret = mipi_dbi_spi_transfer(spi, speed_hz, bpw, data, num); + spi_bus_unlock(spi->controller); free: kfree(buf); |