diff options
author | Xu Yilun <yilun.xu@intel.com> | 2020-06-19 04:43:39 +0300 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2020-06-19 14:56:04 +0300 |
commit | 3c6519736eefebafdf8c82d46f64b214403b5260 (patch) | |
tree | 79f01a2f13756f751d4b69854a998dc13fccd325 /drivers/spi | |
parent | 539afdf969d6ad7ded543d9abf14596aec411fe9 (diff) | |
download | linux-3c6519736eefebafdf8c82d46f64b214403b5260.tar.xz |
spi: altera: use regmap-mmio instead of direct mmio register access
This patch adds support for regmap. It makes preparation for supporting
different ways to access the registers.
Signed-off-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Signed-off-by: Wu Hao <hao.wu@intel.com>
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/1592531021-11412-2-git-send-email-yilun.xu@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/Kconfig | 1 | ||||
-rw-r--r-- | drivers/spi/spi-altera.c | 91 |
2 files changed, 73 insertions, 19 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 357810d6ec2d..4e4513a2006e 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -59,6 +59,7 @@ comment "SPI Master Controller Drivers" config SPI_ALTERA tristate "Altera SPI Controller" + select REGMAP_MMIO help This is the driver for the Altera SPI Controller. diff --git a/drivers/spi/spi-altera.c b/drivers/spi/spi-altera.c index aa9d1a257433..b215bdfb77fd 100644 --- a/drivers/spi/spi-altera.c +++ b/drivers/spi/spi-altera.c @@ -44,7 +44,6 @@ #define ALTERA_SPI_MAX_CS 32 struct altera_spi { - void __iomem *base; int irq; int len; int count; @@ -54,8 +53,43 @@ struct altera_spi { /* data buffers */ const unsigned char *tx; unsigned char *rx; + + struct regmap *regmap; + struct device *dev; +}; + +static const struct regmap_config spi_altera_config = { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, + .fast_io = true, }; +static int altr_spi_writel(struct altera_spi *hw, unsigned int reg, + unsigned int val) +{ + int ret; + + ret = regmap_write(hw->regmap, reg, val); + if (ret) + dev_err(hw->dev, "fail to write reg 0x%x val 0x%x: %d\n", + reg, val, ret); + + return ret; +} + +static int altr_spi_readl(struct altera_spi *hw, unsigned int reg, + unsigned int *val) +{ + int ret; + + ret = regmap_read(hw->regmap, reg, val); + if (ret) + dev_err(hw->dev, "fail to read reg 0x%x: %d\n", reg, ret); + + return ret; +} + static inline struct altera_spi *altera_spi_to_hw(struct spi_device *sdev) { return spi_master_get_devdata(sdev->master); @@ -67,12 +101,13 @@ static void altera_spi_set_cs(struct spi_device *spi, bool is_high) if (is_high) { hw->imr &= ~ALTERA_SPI_CONTROL_SSO_MSK; - writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); - writel(0, hw->base + ALTERA_SPI_SLAVE_SEL); + altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr); + altr_spi_writel(hw, ALTERA_SPI_SLAVE_SEL, 0); } else { - writel(BIT(spi->chip_select), hw->base + ALTERA_SPI_SLAVE_SEL); + altr_spi_writel(hw, ALTERA_SPI_SLAVE_SEL, + BIT(spi->chip_select)); hw->imr |= ALTERA_SPI_CONTROL_SSO_MSK; - writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr); } } @@ -99,14 +134,14 @@ static void altera_spi_tx_word(struct altera_spi *hw) } } - writel(txd, hw->base + ALTERA_SPI_TXDATA); + altr_spi_writel(hw, ALTERA_SPI_TXDATA, txd); } static void altera_spi_rx_word(struct altera_spi *hw) { unsigned int rxd; - rxd = readl(hw->base + ALTERA_SPI_RXDATA); + altr_spi_readl(hw, ALTERA_SPI_RXDATA, &rxd); if (hw->rx) { switch (hw->bytes_per_word) { case 1: @@ -133,6 +168,7 @@ static int altera_spi_txrx(struct spi_master *master, struct spi_device *spi, struct spi_transfer *t) { struct altera_spi *hw = spi_master_get_devdata(master); + u32 val; hw->tx = t->tx_buf; hw->rx = t->rx_buf; @@ -143,7 +179,7 @@ static int altera_spi_txrx(struct spi_master *master, if (hw->irq >= 0) { /* enable receive interrupt */ hw->imr |= ALTERA_SPI_CONTROL_IRRDY_MSK; - writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr); /* send the first byte */ altera_spi_tx_word(hw); @@ -151,9 +187,13 @@ static int altera_spi_txrx(struct spi_master *master, while (hw->count < hw->len) { altera_spi_tx_word(hw); - while (!(readl(hw->base + ALTERA_SPI_STATUS) & - ALTERA_SPI_STATUS_RRDY_MSK)) + for (;;) { + altr_spi_readl(hw, ALTERA_SPI_STATUS, &val); + if (val & ALTERA_SPI_STATUS_RRDY_MSK) + break; + cpu_relax(); + } altera_spi_rx_word(hw); } @@ -175,7 +215,7 @@ static irqreturn_t altera_spi_irq(int irq, void *dev) } else { /* disable receive interrupt */ hw->imr &= ~ALTERA_SPI_CONTROL_IRRDY_MSK; - writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr); spi_finalize_current_transfer(master); } @@ -188,7 +228,9 @@ static int altera_spi_probe(struct platform_device *pdev) struct altera_spi_platform_data *pdata = dev_get_platdata(&pdev->dev); struct altera_spi *hw; struct spi_master *master; + void __iomem *res; int err = -ENODEV; + u32 val; u16 i; master = spi_alloc_master(&pdev->dev, sizeof(struct altera_spi)); @@ -220,19 +262,30 @@ static int altera_spi_probe(struct platform_device *pdev) master->set_cs = altera_spi_set_cs; hw = spi_master_get_devdata(master); + hw->dev = &pdev->dev; /* find and map our resources */ - hw->base = devm_platform_ioremap_resource(pdev, 0); - if (IS_ERR(hw->base)) { - err = PTR_ERR(hw->base); + res = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(res)) { + err = PTR_ERR(res); goto exit; } + + hw->regmap = devm_regmap_init_mmio(&pdev->dev, res, + &spi_altera_config); + if (IS_ERR(hw->regmap)) { + dev_err(&pdev->dev, "regmap mmio init failed\n"); + err = PTR_ERR(hw->regmap); + goto exit; + } + /* program defaults into the registers */ hw->imr = 0; /* disable spi interrupts */ - writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); - writel(0, hw->base + ALTERA_SPI_STATUS); /* clear status reg */ - if (readl(hw->base + ALTERA_SPI_STATUS) & ALTERA_SPI_STATUS_RRDY_MSK) - readl(hw->base + ALTERA_SPI_RXDATA); /* flush rxdata */ + altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr); + altr_spi_writel(hw, ALTERA_SPI_STATUS, 0); /* clear status reg */ + altr_spi_readl(hw, ALTERA_SPI_STATUS, &val); + if (val & ALTERA_SPI_STATUS_RRDY_MSK) + altr_spi_readl(hw, ALTERA_SPI_RXDATA, &val); /* flush rxdata */ /* irq is optional */ hw->irq = platform_get_irq(pdev, 0); if (hw->irq >= 0) { @@ -255,7 +308,7 @@ static int altera_spi_probe(struct platform_device *pdev) } } - dev_info(&pdev->dev, "base %p, irq %d\n", hw->base, hw->irq); + dev_info(&pdev->dev, "base %p, irq %d\n", res, hw->irq); return 0; exit: |