[PATCH] Documentation: spi: Update gpio+bitbang instruction

From: Marco Sirabella
Date: Sun Apr 14 2024 - 02:54:16 EST


The way to do this was changed in
9b00bc7b901f (spi-gpio: Rewrite to use GPIO descriptors)
and there's no real docs outlining this,
update defunct #include "spi-gpio.c" instructions

Signed-off-by: Marco Sirabella <marco@xxxxxxxxxxxxx>
---
drivers/spi/spi-gpio.c | 17 ++++-------------
1 file changed, 4 insertions(+), 13 deletions(-)

diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index 909cce109bba..8c5f88f01db2 100644
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -44,22 +44,13 @@ struct spi_gpio {
* per transferred bit can make performance a problem, this code
* is set up so that you can use it in either of two ways:
*
- * - The slow generic way: set up platform_data to hold the GPIO
+ * - The generic way: set up platform_data to hold the GPIO
* numbers used for MISO/MOSI/SCK, and issue procedure calls for
* each of them. This driver can handle several such busses.
*
- * - The quicker inlined way: only helps with platform GPIO code
- * that inlines operations for constant GPIOs. This can give
- * you tight (fast!) inner loops, but each such bus needs a
- * new driver. You'll define a new C file, with Makefile and
- * Kconfig support; the C code can be a total of six lines:
- *
- * #define DRIVER_NAME "myboard_spi2"
- * #define SPI_MISO_GPIO 119
- * #define SPI_MOSI_GPIO 120
- * #define SPI_SCK_GPIO 121
- * #define SPI_N_CHIPSEL 4
- * #include "spi-gpio.c"
+ * - The inlined way: manually set up and register a gpiod_lookup_table with
+ * the appropriately labelled gpio pins "sck", "mosi", "miso" & an array
+ * named "cs" before calling devm_spi_register_controller (XXX).
*/

#ifndef DRIVER_NAME
--
2.43.2