Unverified Commit 81059366 authored by Alexandru Ardelean's avatar Alexandru Ardelean Committed by Mark Brown
Browse files

spi: tegra114: change format for `spi_set_cs_timing()` function 



The initial version of `spi_set_cs_timing()` was implemented with
consideration only for clock-cycles as delay.

For cases like `CS setup` time, it's sometimes needed that micro-seconds
(or nano-seconds) are required, or sometimes even longer delays, for cases
where the device needs a little longer to start transferring that after CS
is asserted.

Signed-off-by: default avatarAlexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-15-alexandru.ardelean@analog.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 8e319dd5

drivers/spi/spi-tegra114.c

+20 −2
Original line number Diff line number Diff line
@@ -723,15 +723,31 @@ static void tegra_spi_deinit_dma_param(struct tegra_spi_data *tspi, 
	dma_release_channel(dma_chan);

}



static void tegra_spi_set_hw_cs_timing(struct spi_device *spi, u8 setup_dly,

				       u8 hold_dly, u8 inactive_dly)

static int tegra_spi_set_hw_cs_timing(struct spi_device *spi,

				      struct spi_delay *setup,

				      struct spi_delay *hold,

				      struct spi_delay *inactive)

{

	struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master);

	u8 setup_dly, hold_dly, inactive_dly;

	u32 setup_hold;

	u32 spi_cs_timing;

	u32 inactive_cycles;

	u8 cs_state;



	if ((setup && setup->unit != SPI_DELAY_UNIT_SCK) ||

	    (hold && hold->unit != SPI_DELAY_UNIT_SCK) ||

	    (inactive && inactive->unit != SPI_DELAY_UNIT_SCK)) {

		dev_err(&spi->dev,

			"Invalid delay unit %d, should be SPI_DELAY_UNIT_SCK\n",

			SPI_DELAY_UNIT_SCK);

		return -EINVAL;

	}



	setup_dly = setup ? setup->value : 0;

	hold_dly = hold ? hold->value : 0;

	inactive_dly = inactive ? inactive->value : 0;



	setup_dly = min_t(u8, setup_dly, MAX_SETUP_HOLD_CYCLES);

	hold_dly = min_t(u8, hold_dly, MAX_SETUP_HOLD_CYCLES);

	if (setup_dly && hold_dly) {
@@ -758,6 +774,8 @@ static void tegra_spi_set_hw_cs_timing(struct spi_device *spi, u8 setup_dly, 
		tspi->spi_cs_timing2 = spi_cs_timing;

		tegra_spi_writel(tspi, spi_cs_timing, SPI_CS_TIMING2);

	}



	return 0;

}



static u32 tegra_spi_setup_transfer_one(struct spi_device *spi,

drivers/spi/spi.c

+10 −6
Original line number Diff line number Diff line
@@ -3269,15 +3269,19 @@ EXPORT_SYMBOL_GPL(spi_setup); 
/**

 * spi_set_cs_timing - configure CS setup, hold, and inactive delays

 * @spi: the device that requires specific CS timing configuration

 * @setup: CS setup time in terms of clock count

 * @hold: CS hold time in terms of clock count

 * @inactive_dly: CS inactive delay between transfers in terms of clock count

 * @setup: CS setup time specified via @spi_delay

 * @hold: CS hold time specified via @spi_delay

 * @inactive: CS inactive delay between transfers specified via @spi_delay

 *

 * Return: zero on success, else a negative error code.

 */

void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold,

		       u8 inactive_dly)

int spi_set_cs_timing(struct spi_device *spi, struct spi_delay *setup,

		      struct spi_delay *hold, struct spi_delay *inactive)

{

	if (spi->controller->set_cs_timing)

		spi->controller->set_cs_timing(spi, setup, hold, inactive_dly);

		return spi->controller->set_cs_timing(spi, setup, hold,

						      inactive);

	return -ENOTSUPP;

}

EXPORT_SYMBOL_GPL(spi_set_cs_timing);

include/linux/spi/spi.h

+6 −3
Original line number Diff line number Diff line
@@ -524,8 +524,8 @@ struct spi_controller { 
	 * to configure specific CS timing through spi_set_cs_timing() after

	 * spi_setup().

	 */

	void (*set_cs_timing)(struct spi_device *spi, u8 setup_clk_cycles,

			      u8 hold_clk_cycles, u8 inactive_clk_cycles);

	int (*set_cs_timing)(struct spi_device *spi, struct spi_delay *setup,

			     struct spi_delay *hold, struct spi_delay *inactive);



	/* bidirectional bulk transfers

	 *
@@ -1068,7 +1068,10 @@ static inline void spi_message_free(struct spi_message *m) 
	kfree(m);

}



extern void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold, u8 inactive_dly);

extern int spi_set_cs_timing(struct spi_device *spi,

			     struct spi_delay *setup,

			     struct spi_delay *hold,

			     struct spi_delay *inactive);



extern int spi_setup(struct spi_device *spi);

extern int spi_async(struct spi_device *spi, struct spi_message *message);

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