From 17dbda0c31093008e68f7a39c9cf9e41eab3cd1e Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Wed, 2 Aug 2017 21:39:06 +0200 Subject: spi: imx: add error checking MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This makes it possible that the xchg_single callbacks return an error code that is then passed to the caller of spi_transfer. There is no change in behaviour intended as up to now the callbacks always return 0. Signed-off-by: Uwe Kleine-König Signed-off-by: Lucas Stach --- drivers/spi/imx_spi.c | 77 ++++++++++++++++++++++++++++++++------------------- 1 file changed, 48 insertions(+), 29 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/imx_spi.c b/drivers/spi/imx_spi.c index 876699a02d..97a2091969 100644 --- a/drivers/spi/imx_spi.c +++ b/drivers/spi/imx_spi.c @@ -38,8 +38,8 @@ struct imx_spi { void __iomem *regs; struct clk *clk; - unsigned int (*xchg_single)(struct imx_spi *imx, u32 data); - void (*do_transfer)(struct spi_device *spi); + int (*xchg_single)(struct imx_spi *imx, u32 txdata, u32 *rxdata); + int (*do_transfer)(struct spi_device *spi); void (*chipselect)(struct spi_device *spi, int active); const void *tx_buf; @@ -49,8 +49,8 @@ struct imx_spi { }; struct spi_imx_devtype_data { - unsigned int (*xchg_single)(struct imx_spi *imx, u32 data); - void (*do_transfer)(struct spi_device *spi); + int (*xchg_single)(struct imx_spi *imx, u32 txdata, u32 *rxdata); + int (*do_transfer)(struct spi_device *spi); void (*chipselect)(struct spi_device *spi, int active); void (*init)(struct imx_spi *imx); }; @@ -86,13 +86,13 @@ static unsigned int imx_spi_maybe_reverse_bits(struct spi_device *spi, unsigned return result; } -static unsigned int cspi_0_0_xchg_single(struct imx_spi *imx, unsigned int data) +static int cspi_0_0_xchg_single(struct imx_spi *imx, u32 txdata, u32 *rxdata) { void __iomem *base = imx->regs; unsigned int cfg_reg = readl(base + CSPI_0_0_CTRL); - writel(data, base + CSPI_0_0_TXDATA); + writel(txdata, base + CSPI_0_0_TXDATA); cfg_reg |= CSPI_0_0_CTRL_XCH; @@ -100,7 +100,9 @@ static unsigned int cspi_0_0_xchg_single(struct imx_spi *imx, unsigned int data) while (!(readl(base + CSPI_0_0_INT) & CSPI_0_0_STAT_RR)); - return readl(base + CSPI_0_0_RXDATA); + *rxdata = readl(base + CSPI_0_0_RXDATA); + + return 0; } static void cspi_0_0_chipselect(struct spi_device *spi, int is_active) @@ -152,13 +154,13 @@ static void cspi_0_0_init(struct imx_spi *imx) } while (readl(base + CSPI_0_0_RESET) & CSPI_0_0_RESET_START); } -static unsigned int cspi_0_7_xchg_single(struct imx_spi *imx, unsigned int data) +static int cspi_0_7_xchg_single(struct imx_spi *imx, u32 txdata, u32 *rxdata) { void __iomem *base = imx->regs; unsigned int cfg_reg = readl(base + CSPI_0_7_CTRL); - writel(data, base + CSPI_0_7_TXDATA); + writel(txdata, base + CSPI_0_7_TXDATA); cfg_reg |= CSPI_0_7_CTRL_XCH; @@ -167,7 +169,8 @@ static unsigned int cspi_0_7_xchg_single(struct imx_spi *imx, unsigned int data) while (!(readl(base + CSPI_0_7_STAT) & CSPI_0_7_STAT_RR)) ; - return readl(base + CSPI_0_7_RXDATA); + *rxdata = readl(base + CSPI_0_7_RXDATA); + return 0; } /* MX1, MX31, MX35, MX51 CSPI */ @@ -242,15 +245,17 @@ static void cspi_0_7_init(struct imx_spi *imx) readl(base + CSPI_0_7_RXDATA); } -static unsigned int cspi_2_3_xchg_single(struct imx_spi *imx, unsigned int data) +static int cspi_2_3_xchg_single(struct imx_spi *imx, u32 txdata, u32 *rxdata) { void __iomem *base = imx->regs; - writel(data, base + CSPI_2_3_TXDATA); + writel(txdata, base + CSPI_2_3_TXDATA); while (!(readl(base + CSPI_2_3_STAT) & CSPI_2_3_STAT_RR)); - return readl(base + CSPI_2_3_RXDATA); + *rxdata = readl(base + CSPI_2_3_RXDATA); + + return 0; } static unsigned int cspi_2_3_clkdiv(unsigned int fin, unsigned int fspi) @@ -336,16 +341,20 @@ static void cspi_2_3_chipselect(struct spi_device *spi, int is_active) gpio_set_value(gpio, gpio_cs); } -static u32 imx_xchg_single(struct spi_device *spi, u32 tx_val) +static int imx_xchg_single(struct spi_device *spi, u32 tx_val, u32* rx_val) { - u32 rx_val; struct imx_spi *imx = container_of(spi->master, struct imx_spi, master); - + u32 local_rx_val; + int ret; tx_val = imx_spi_maybe_reverse_bits(spi, tx_val); - rx_val = imx->xchg_single(imx, tx_val); + ret = imx->xchg_single(imx, tx_val, &local_rx_val); + if (ret) + return ret; - return imx_spi_maybe_reverse_bits(spi, rx_val); + *rx_val = imx_spi_maybe_reverse_bits(spi, local_rx_val); + + return 0; } static void cspi_2_3_init(struct imx_spi *imx) @@ -355,18 +364,21 @@ static void cspi_2_3_init(struct imx_spi *imx) writel(0, base + CSPI_2_3_CTRL); } -static void imx_spi_do_transfer(struct spi_device *spi) +static int imx_spi_do_transfer(struct spi_device *spi) { struct imx_spi *imx = container_of(spi->master, struct imx_spi, master); unsigned i; + u32 rx_val; + int ret; if (imx->bits_per_word <= 8) { const u8 *tx_buf = imx->tx_buf; u8 *rx_buf = imx->rx_buf; - u8 rx_val; for (i = 0; i < imx->xfer_len; i++) { - rx_val = imx_xchg_single(spi, tx_buf ? tx_buf[i] : 0); + ret = imx_xchg_single(spi, tx_buf ? tx_buf[i] : 0, &rx_val); + if (ret) + return ret; if (rx_buf) rx_buf[i] = rx_val; @@ -374,10 +386,11 @@ static void imx_spi_do_transfer(struct spi_device *spi) } else if (imx->bits_per_word <= 16) { const u16 *tx_buf = imx->tx_buf; u16 *rx_buf = imx->rx_buf; - u16 rx_val; for (i = 0; i < imx->xfer_len >> 1; i++) { - rx_val = imx_xchg_single(spi, tx_buf ? tx_buf[i] : 0); + ret = imx_xchg_single(spi, tx_buf ? tx_buf[i] : 0, &rx_val); + if (ret) + return ret; if (rx_buf) rx_buf[i] = rx_val; @@ -385,15 +398,18 @@ static void imx_spi_do_transfer(struct spi_device *spi) } else if (imx->bits_per_word <= 32) { const u32 *tx_buf = imx->tx_buf; u32 *rx_buf = imx->rx_buf; - u32 rx_val; for (i = 0; i < imx->xfer_len >> 2; i++) { - rx_val = imx_xchg_single(spi, tx_buf ? tx_buf[i] : 0); + ret = imx_xchg_single(spi, tx_buf ? tx_buf[i] : 0, &rx_val); + if (ret) + return ret; if (rx_buf) rx_buf[i] = rx_val; } } + + return 0; } static int cspi_2_3_xchg_burst(struct spi_device *spi) @@ -448,7 +464,7 @@ static int cspi_2_3_xchg_burst(struct spi_device *spi) return now; } -static void cspi_2_3_do_transfer(struct spi_device *spi) +static int cspi_2_3_do_transfer(struct spi_device *spi) { struct imx_spi *imx = container_of(spi->master, struct imx_spi, master); u32 ctrl; @@ -457,14 +473,14 @@ static void cspi_2_3_do_transfer(struct spi_device *spi) while (cspi_2_3_xchg_burst(spi) > 0); if (!imx->xfer_len) - return; + return 0; ctrl = readl(imx->regs + CSPI_2_3_CTRL); ctrl &= ~(0xfff << CSPI_2_3_CTRL_BL_OFFSET); ctrl |= (spi->bits_per_word - 1) << CSPI_2_3_CTRL_BL_OFFSET; writel(ctrl, imx->regs + CSPI_2_3_CTRL); - imx_spi_do_transfer(spi); + return imx_spi_do_transfer(spi); } static int imx_spi_transfer(struct spi_device *spi, struct spi_message *mesg) @@ -473,6 +489,7 @@ static int imx_spi_transfer(struct spi_device *spi, struct spi_message *mesg) struct spi_transfer *t; unsigned int cs_change; const int nsecs = 50; + int ret; imx->chipselect(spi, 1); @@ -494,7 +511,9 @@ static int imx_spi_transfer(struct spi_device *spi, struct spi_message *mesg) imx->rx_buf = t->rx_buf; imx->xfer_len = t->len; imx->bits_per_word = spi->bits_per_word; - imx->do_transfer(spi); + ret = imx->do_transfer(spi); + if (ret) + return ret; mesg->actual_length += t->len; -- cgit v1.2.3