spi: core: add hook flash_read_supported to spi_master (7ba2f275) · Commits · 戴 / test

If hook spi_flash_read is implemented the fast flash read feature is enabled for all devices attached to the respective master. In most cases there is just one flash chip, however there are also devices with more than one flash chip, namely some WiFi routers. Then the fast flash read feature can be used for the first chip only. OpenWRT implemented an own handling of this case, using controller_data element of spi_device to hold the information whether fast flash read can be used for a device. This patch adds hook flash_read_supported to spi_master which is used to extend spi_flash_read_supported() by checking whether the fast flash read feature can be used for a specific spi_device. If the hook is not implemented the default behavior is to allow fast flash read for all devices (if spi_flash_read is implemented). Signed-off-by:

Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by:

Mark Brown <broonie@kernel.org>

include/linux/spi/spi.h

+5 −1

Original line number	Diff line number	Diff line
		@@ -372,6 +372,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
		* @unprepare_message: undo any work done by prepare_message().
		* @spi_flash_read: to support spi-controller hardwares that provide
		* accelerated interface to read from flash devices.
		* @flash_read_supported: spi device supports flash read
		* @cs_gpios: Array of GPIOs to use as chip select lines; one per CS
		* number. Any individual value may be -ENOENT for CS lines that
		* are not GPIOs (driven by the SPI controller itself).
		@@ -529,6 +530,7 @@ struct spi_master {
		struct spi_message *message);
		int (spi_flash_read)(struct spi_device spi,
		struct spi_flash_read_message *msg);
		bool (flash_read_supported)(struct spi_device spi);

		/*
		* These hooks are for drivers that use a generic implementation
		@@ -1158,7 +1160,9 @@ struct spi_flash_read_message {
		/* SPI core interface for flash read support */
		static inline bool spi_flash_read_supported(struct spi_device *spi)
		{
		return spi->master->spi_flash_read ? true : false;
		return spi->master->spi_flash_read &&
		(!spi->master->flash_read_supported \|\|
		spi->master->flash_read_supported(spi));
		}

		int spi_flash_read(struct spi_device *spi,

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