diff options
Diffstat (limited to 'drivers/spi/spi-imx.c')
| -rw-r--r-- | drivers/spi/spi-imx.c | 51 |
1 files changed, 35 insertions, 16 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index deb782f6556c..9a7c62f471dc 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -173,15 +173,16 @@ static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192, /* MX21, MX27 */ static unsigned int spi_imx_clkdiv_1(unsigned int fin, - unsigned int fspi, unsigned int max) + unsigned int fspi, unsigned int max, unsigned int *fres) { int i; for (i = 2; i < max; i++) if (fspi * mxc_clkdivs[i] >= fin) - return i; + break; - return max; + *fres = fin / mxc_clkdivs[i]; + return i; } /* MX1, MX31, MX35, MX51 CSPI */ @@ -210,7 +211,7 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, struct spi_transfer *transfer) { struct spi_imx_data *spi_imx = spi_master_get_devdata(master); - unsigned int bpw; + unsigned int bpw, i; if (!master->dma_rx) return false; @@ -227,12 +228,16 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, if (bpw != 1 && bpw != 2 && bpw != 4) return false; - if (transfer->len < spi_imx->wml * bpw) - return false; + for (i = spi_imx_get_fifosize(spi_imx) / 2; i > 0; i--) { + if (!(transfer->len % (i * bpw))) + break; + } - if (transfer->len % (spi_imx->wml * bpw)) + if (i == 0) return false; + spi_imx->wml = i; + return true; } @@ -442,6 +447,7 @@ static void mx51_ecspi_reset(struct spi_imx_data *spi_imx) #define MX31_CSPICTRL_ENABLE (1 << 0) #define MX31_CSPICTRL_MASTER (1 << 1) #define MX31_CSPICTRL_XCH (1 << 2) +#define MX31_CSPICTRL_SMC (1 << 3) #define MX31_CSPICTRL_POL (1 << 4) #define MX31_CSPICTRL_PHA (1 << 5) #define MX31_CSPICTRL_SSCTL (1 << 6) @@ -452,6 +458,10 @@ static void mx51_ecspi_reset(struct spi_imx_data *spi_imx) #define MX35_CSPICTRL_CS_SHIFT 12 #define MX31_CSPICTRL_DR_SHIFT 16 +#define MX31_CSPI_DMAREG 0x10 +#define MX31_DMAREG_RH_DEN (1<<4) +#define MX31_DMAREG_TH_DEN (1<<1) + #define MX31_CSPISTATUS 0x14 #define MX31_STATUS_RR (1 << 3) @@ -511,6 +521,9 @@ static int mx31_config(struct spi_device *spi, struct spi_imx_config *config) (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT : MX31_CSPICTRL_CS_SHIFT); + if (spi_imx->usedma) + reg |= MX31_CSPICTRL_SMC; + writel(reg, spi_imx->base + MXC_CSPICTRL); reg = readl(spi_imx->base + MX31_CSPI_TESTREG); @@ -520,6 +533,13 @@ static int mx31_config(struct spi_device *spi, struct spi_imx_config *config) reg &= ~MX31_TEST_LBC; writel(reg, spi_imx->base + MX31_CSPI_TESTREG); + if (spi_imx->usedma) { + /* configure DMA requests when RXFIFO is half full and + when TXFIFO is half empty */ + writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN, + spi_imx->base + MX31_CSPI_DMAREG); + } + return 0; } @@ -574,9 +594,12 @@ static int mx21_config(struct spi_device *spi, struct spi_imx_config *config) struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER; unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18; + unsigned int clk; + + reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max, &clk) + << MX21_CSPICTRL_DR_SHIFT; + spi_imx->spi_bus_clk = clk; - reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) << - MX21_CSPICTRL_DR_SHIFT; reg |= config->bpw - 1; if (spi->mode & SPI_CPHA) @@ -818,10 +841,6 @@ static int spi_imx_dma_configure(struct spi_master *master, struct dma_slave_config rx = {}, tx = {}; struct spi_imx_data *spi_imx = spi_master_get_devdata(master); - if (bytes_per_word == spi_imx->bytes_per_word) - /* Same as last time */ - return 0; - switch (bytes_per_word) { case 4: buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES; @@ -1244,10 +1263,10 @@ static int spi_imx_probe(struct platform_device *pdev) spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per); /* - * Only validated on i.mx6 now, can remove the constrain if validated on - * other chips. + * Only validated on i.mx35 and i.mx6 now, can remove the constraint + * if validated on other chips. */ - if (is_imx51_ecspi(spi_imx)) { + if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx)) { ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master); if (ret == -EPROBE_DEFER) goto out_clk_put; |