From 95aa28da81cb6bbd13c70c41460c2d24faf24990 Mon Sep 17 00:00:00 2001 From: John Crispin Date: Sun, 22 Nov 2015 11:48:57 +0000 Subject: [PATCH] ramips: move rt2880 spi clock and reset init code to spi_prepare_message before spi transfer. use spi_prepare_message to setup spi hardware. it will setup MSB, spi mode and speed remove sys_freq member and speed check code Signed-off-by: Michael Lee SVN-Revision: 47578 --- ...SPI-ralink-add-Ralink-SoC-spi-driver.patch | 130 +++++++++--------- 1 file changed, 62 insertions(+), 68 deletions(-) diff --git a/target/linux/ramips/patches-3.18/0050-SPI-ralink-add-Ralink-SoC-spi-driver.patch b/target/linux/ramips/patches-3.18/0050-SPI-ralink-add-Ralink-SoC-spi-driver.patch index 418a09416188..862e24c3681e 100644 --- a/target/linux/ramips/patches-3.18/0050-SPI-ralink-add-Ralink-SoC-spi-driver.patch +++ b/target/linux/ramips/patches-3.18/0050-SPI-ralink-add-Ralink-SoC-spi-driver.patch @@ -41,7 +41,7 @@ Acked-by: John Crispin spi-s3c24xx-hw-$(CONFIG_SPI_S3C24XX_FIQ) += spi-s3c24xx-fiq.o --- /dev/null +++ b/drivers/spi/spi-rt2880.c -@@ -0,0 +1,539 @@ +@@ -0,0 +1,533 @@ +/* + * spi-rt2880.c -- Ralink RT288x/RT305x SPI controller driver + * @@ -172,8 +172,7 @@ Acked-by: John Crispin +struct rt2880_spi { + struct spi_master *master; + void __iomem *base; -+ unsigned int sys_freq; -+ unsigned int speed; ++ u32 speed; + u16 wait_loops; + u16 mode; + struct clk *clk; @@ -209,61 +208,33 @@ Acked-by: John Crispin + iowrite32((ioread32(addr) & ~mask), addr); +} + -+static int rt2880_spi_baudrate_set(struct spi_device *spi, unsigned int speed) ++static u32 rt2880_spi_baudrate_get(struct spi_device *spi, unsigned int speed) +{ + struct rt2880_spi *rs = spidev_to_rt2880_spi(spi); + u32 rate; + u32 prescale; -+ u32 reg; -+ -+ dev_dbg(&spi->dev, "speed:%u\n", speed); + + /* + * the supported rates are: 2, 4, 8, ... 128 + * round up as we look for equal or less speed + */ -+ rate = DIV_ROUND_UP(rs->sys_freq, speed); -+ dev_dbg(&spi->dev, "rate-1:%u\n", rate); ++ rate = DIV_ROUND_UP(clk_get_rate(rs->clk), speed); + rate = roundup_pow_of_two(rate); -+ dev_dbg(&spi->dev, "rate-2:%u\n", rate); + + /* Convert the rate to SPI clock divisor value. */ + prescale = ilog2(rate / 2); -+ dev_dbg(&spi->dev, "prescale:%u\n", prescale); -+ -+ reg = rt2880_spi_read(rs, RAMIPS_SPI_CFG); -+ reg = ((reg & ~SPICFG_SPICLK_PRESCALE_MASK) | prescale); -+ rt2880_spi_write(rs, RAMIPS_SPI_CFG, reg); + + /* some tolerance. double and add 100 */ + rs->wait_loops = (8 * HZ * loops_per_jiffy) / + (clk_get_rate(rs->clk) / rate); + rs->wait_loops = (rs->wait_loops << 1) + 100; + rs->speed = speed; -+ return 0; -+} + -+/* -+ * called only when no transfer is active on the bus -+ */ -+static int -+rt2880_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) -+{ -+ struct rt2880_spi *rs = spidev_to_rt2880_spi(spi); -+ unsigned int speed = spi->max_speed_hz; -+ int rc; -+ -+ if ((t != NULL) && t->speed_hz) -+ speed = t->speed_hz; ++ dev_dbg(&spi->dev, "speed: %lu/%u, rate: %u, prescal: %u, loops: %hu\n", ++ clk_get_rate(rs->clk) / rate, speed, rate, prescale, ++ rs->wait_loops); + -+ if (rs->speed != speed) { -+ dev_dbg(&spi->dev, "speed_hz:%u\n", speed); -+ rc = rt2880_spi_baudrate_set(spi, speed); -+ if (rc) -+ return rc; -+ } -+ -+ return 0; ++ return prescale; +} + +static u32 get_arbiter_offset(struct spi_master *master) @@ -345,15 +316,9 @@ Acked-by: John Crispin + struct rt2880_spi *rs = spi_master_get_devdata(master); + struct spi_device *spi = m->spi; + struct spi_transfer *t = NULL; -+ int par_override = 0; + int status = 0; + int cs_active = 0; + -+ /* Load defaults */ -+ status = rt2880_spi_setup_transfer(spi, NULL); -+ if (status < 0) -+ goto msg_done; -+ + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) { + dev_err(&spi->dev, @@ -362,23 +327,6 @@ Acked-by: John Crispin + goto msg_done; + } + -+ if (t->speed_hz && t->speed_hz < (rs->sys_freq / 128)) { -+ dev_err(&spi->dev, -+ "message rejected: device min speed (%d Hz) exceeds required transfer speed (%d Hz)\n", -+ (rs->sys_freq / 128), t->speed_hz); -+ status = -EIO; -+ goto msg_done; -+ } -+ -+ if (par_override || t->speed_hz || t->bits_per_word) { -+ par_override = 1; -+ status = rt2880_spi_setup_transfer(spi, t); -+ if (status < 0) -+ goto msg_done; -+ if (!t->speed_hz && !t->bits_per_word) -+ par_override = 0; -+ } -+ + if (!cs_active) { + rt2880_spi_set_cs(rs, 1); + cs_active = 1; @@ -465,12 +413,60 @@ Acked-by: John Crispin + return 0; +} + -+static void rt2880_spi_reset(struct rt2880_spi *rs) ++static int rt2880_spi_prepare_message(struct spi_master *master, ++ struct spi_message *msg) +{ -+ rt2880_spi_write(rs, RAMIPS_SPI_CFG, -+ SPICFG_MSBFIRST | SPICFG_TXCLKEDGE_FALLING | -+ SPICFG_SPICLK_DIV16 | SPICFG_SPICLKPOL); -+ rt2880_spi_write(rs, RAMIPS_SPI_CTL, SPICTL_HIZSDO | SPICTL_SPIENA); ++ struct rt2880_spi *rs = spi_master_get_devdata(master); ++ struct spi_device *spi = msg->spi; ++ u32 reg; ++ ++ if ((rs->mode == spi->mode) && (rs->speed == spi->max_speed_hz)) ++ return 0; ++ ++#if 0 ++ /* set spido to tri-state */ ++ rt2880_spi_setbits(rs, RAMIPS_SPI_CTL, SPICTL_HIZSDO); ++#endif ++ ++ reg = rt2880_spi_read(rs, RAMIPS_SPI_CFG); ++ ++ reg &= ~(SPICFG_MSBFIRST | SPICFG_SPICLKPOL | ++ SPICFG_RXCLKEDGE_FALLING | ++ SPICFG_TXCLKEDGE_FALLING | ++ SPICFG_SPICLK_PRESCALE_MASK); ++ ++ /* MSB */ ++ if (!(spi->mode & SPI_LSB_FIRST)) ++ reg |= SPICFG_MSBFIRST; ++ ++ /* spi mode */ ++ switch (spi->mode & (SPI_CPOL | SPI_CPHA)) { ++ case SPI_MODE_0: ++ reg |= SPICFG_TXCLKEDGE_FALLING; ++ break; ++ case SPI_MODE_1: ++ reg |= SPICFG_RXCLKEDGE_FALLING; ++ break; ++ case SPI_MODE_2: ++ reg |= SPICFG_SPICLKPOL | SPICFG_RXCLKEDGE_FALLING; ++ break; ++ case SPI_MODE_3: ++ reg |= SPICFG_SPICLKPOL | SPICFG_TXCLKEDGE_FALLING; ++ break; ++ } ++ rs->mode = spi->mode; ++ ++#if 0 ++ /* set spiclk and spiena to tri-state */ ++ reg |= SPICFG_HIZSPI; ++#endif ++ ++ /* clock divide */ ++ reg |= rt2880_spi_baudrate_get(spi, spi->max_speed_hz); ++ ++ rt2880_spi_write(rs, RAMIPS_SPI_CFG, reg); ++ ++ return 0; +} + +static int rt2880_spi_probe(struct platform_device *pdev) @@ -511,6 +507,7 @@ Acked-by: John Crispin + master->max_speed_hz = clk_get_rate(clk) / 2; + master->flags = SPI_MASTER_HALF_DUPLEX; + master->setup = rt2880_spi_setup; ++ master->prepare_message = rt2880_spi_prepare_message; + master->transfer_one_message = rt2880_spi_transfer_one_message; + master->num_chipselect = RALINK_NUM_CHIPSELECTS; + @@ -520,12 +517,9 @@ Acked-by: John Crispin + rs->master = master; + rs->base = base; + rs->clk = clk; -+ rs->sys_freq = clk_get_rate(rs->clk); -+ dev_dbg(&pdev->dev, "sys_freq: %u\n", rs->sys_freq); + + device_reset(&pdev->dev); + -+ rt2880_spi_reset(rs); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret < 0) { -- 2.30.2