Unverified Commit 9b76ef39 authored by Sowjanya Komatineni's avatar Sowjanya Komatineni Committed by Mark Brown
Browse files

spi: tegra114: add support for HW CS timing 



This patch implements set_cs_timing SPI controller method to allow
SPI client driver to configure device specific SPI CS timings.

Signed-off-by: default avatarSowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 1bf9f3c9

drivers/spi/spi-tegra114.c

+46 −2
Original line number Diff line number Diff line
@@ -95,8 +95,10 @@ 
		(reg = (((val) & 0x1) << ((cs) * 8 + 5)) |	\

			((reg) & ~(1 << ((cs) * 8 + 5))))

#define SPI_SET_CYCLES_BETWEEN_PACKETS(reg, cs, val)		\

		(reg = (((val) & 0xF) << ((cs) * 8)) |		\

			((reg) & ~(0xF << ((cs) * 8))))

		(reg = (((val) & 0x1F) << ((cs) * 8)) |		\

			((reg) & ~(0x1F << ((cs) * 8))))

#define MAX_SETUP_HOLD_CYCLES			16

#define MAX_INACTIVE_CYCLES			32



#define SPI_TRANS_STATUS			0x010

#define SPI_BLK_CNT(val)			(((val) >> 0) & 0xFFFF)
@@ -206,6 +208,8 @@ struct tegra_spi_data { 
	u32					command1_reg;

	u32					dma_control_reg;

	u32					def_command1_reg;

	u32					spi_cs_timing1;

	u32					spi_cs_timing2;



	struct completion			xfer_completion;

	struct spi_transfer			*curr_xfer;
@@ -723,6 +727,43 @@ 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)

{

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

	u32 setup_hold;

	u32 spi_cs_timing;

	u32 inactive_cycles;

	u8 cs_state;



	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) {

		setup_hold = SPI_SETUP_HOLD(setup_dly - 1, hold_dly - 1);

		spi_cs_timing = SPI_CS_SETUP_HOLD(tspi->spi_cs_timing1,

						  spi->chip_select,

						  setup_hold);

		if (tspi->spi_cs_timing1 != spi_cs_timing) {

			tspi->spi_cs_timing1 = spi_cs_timing;

			tegra_spi_writel(tspi, spi_cs_timing, SPI_CS_TIMING1);

		}

	}



	inactive_cycles = min_t(u8, inactive_dly, MAX_INACTIVE_CYCLES);

	if (inactive_cycles)

		inactive_cycles--;

	cs_state = inactive_cycles ? 0 : 1;

	spi_cs_timing = tspi->spi_cs_timing2;

	SPI_SET_CS_ACTIVE_BETWEEN_PACKETS(spi_cs_timing, spi->chip_select,

					  cs_state);

	SPI_SET_CYCLES_BETWEEN_PACKETS(spi_cs_timing, spi->chip_select,

				       inactive_cycles);

	if (tspi->spi_cs_timing2 != spi_cs_timing) {

		tspi->spi_cs_timing2 = spi_cs_timing;

		tegra_spi_writel(tspi, spi_cs_timing, SPI_CS_TIMING2);

	}

}



static u32 tegra_spi_setup_transfer_one(struct spi_device *spi,

					struct spi_transfer *t,

					bool is_first_of_msg,
@@ -1232,6 +1273,7 @@ static int tegra_spi_probe(struct platform_device *pdev) 
	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);

	master->setup = tegra_spi_setup;

	master->transfer_one_message = tegra_spi_transfer_one_message;

	master->set_cs_timing = tegra_spi_set_hw_cs_timing;

	master->num_chipselect = MAX_CHIP_SELECT;

	master->auto_runtime_pm = true;

	bus_num = of_alias_get_id(pdev->dev.of_node, "spi");
@@ -1307,6 +1349,8 @@ static int tegra_spi_probe(struct platform_device *pdev) 
	reset_control_deassert(tspi->rst);

	tspi->def_command1_reg  = SPI_M_S;

	tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1);

	tspi->spi_cs_timing1 = tegra_spi_readl(tspi, SPI_CS_TIMING1);

	tspi->spi_cs_timing2 = tegra_spi_readl(tspi, SPI_CS_TIMING2);

	pm_runtime_put(&pdev->dev);

	ret = request_threaded_irq(tspi->irq, tegra_spi_isr,

				   tegra_spi_isr_thread, IRQF_ONESHOT,