diff options
Diffstat (limited to 'drivers/spi/spi-omap2-mcspi.c')
-rw-r--r-- | drivers/spi/spi-omap2-mcspi.c | 250 |
1 files changed, 189 insertions, 61 deletions
diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 1a75aef..5994039 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -38,13 +38,15 @@ #include <linux/pm_runtime.h> #include <linux/of.h> #include <linux/of_device.h> -#include <linux/pinctrl/consumer.h> +#include <linux/gcd.h> #include <linux/spi/spi.h> #include <linux/platform_data/spi-omap2-mcspi.h> #define OMAP2_MCSPI_MAX_FREQ 48000000 +#define OMAP2_MCSPI_MAX_FIFODEPTH 64 +#define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF #define SPI_AUTOSUSPEND_TIMEOUT 2000 #define OMAP2_MCSPI_REVISION 0x00 @@ -54,6 +56,7 @@ #define OMAP2_MCSPI_WAKEUPENABLE 0x20 #define OMAP2_MCSPI_SYST 0x24 #define OMAP2_MCSPI_MODULCTRL 0x28 +#define OMAP2_MCSPI_XFERLEVEL 0x7c /* per-channel banks, 0x14 bytes each, first is: */ #define OMAP2_MCSPI_CHCONF0 0x2c @@ -63,6 +66,7 @@ #define OMAP2_MCSPI_RX0 0x3c /* per-register bitmasks: */ +#define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17) #define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0) #define OMAP2_MCSPI_MODULCTRL_MS BIT(2) @@ -83,10 +87,13 @@ #define OMAP2_MCSPI_CHCONF_IS BIT(18) #define OMAP2_MCSPI_CHCONF_TURBO BIT(19) #define OMAP2_MCSPI_CHCONF_FORCE BIT(20) +#define OMAP2_MCSPI_CHCONF_FFET BIT(27) +#define OMAP2_MCSPI_CHCONF_FFER BIT(28) #define OMAP2_MCSPI_CHSTAT_RXS BIT(0) #define OMAP2_MCSPI_CHSTAT_TXS BIT(1) #define OMAP2_MCSPI_CHSTAT_EOT BIT(2) +#define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3) #define OMAP2_MCSPI_CHCTRL_EN BIT(0) @@ -102,6 +109,9 @@ struct omap2_mcspi_dma { struct completion dma_tx_completion; struct completion dma_rx_completion; + + char dma_rx_ch_name[14]; + char dma_tx_ch_name[14]; }; /* use PIO for small transfers, avoiding DMA setup/teardown overhead and @@ -129,6 +139,7 @@ struct omap2_mcspi { struct omap2_mcspi_dma *dma_channels; struct device *dev; struct omap2_mcspi_regs ctx; + int fifo_depth; unsigned int pin_dir:1; }; @@ -187,6 +198,16 @@ static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val) mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0); } +static inline int mcspi_bytes_per_word(int word_len) +{ + if (word_len <= 8) + return 1; + else if (word_len <= 16) + return 2; + else /* word_len <= 32 */ + return 4; +} + static void omap2_mcspi_set_dma_req(const struct spi_device *spi, int is_read, int enable) { @@ -248,6 +269,58 @@ static void omap2_mcspi_set_master_mode(struct spi_master *master) ctx->modulctrl = l; } +static void omap2_mcspi_set_fifo(const struct spi_device *spi, + struct spi_transfer *t, int enable) +{ + struct spi_master *master = spi->master; + struct omap2_mcspi_cs *cs = spi->controller_state; + struct omap2_mcspi *mcspi; + unsigned int wcnt; + int fifo_depth, bytes_per_word; + u32 chconf, xferlevel; + + mcspi = spi_master_get_devdata(master); + + chconf = mcspi_cached_chconf0(spi); + if (enable) { + bytes_per_word = mcspi_bytes_per_word(cs->word_len); + if (t->len % bytes_per_word != 0) + goto disable_fifo; + + fifo_depth = gcd(t->len, OMAP2_MCSPI_MAX_FIFODEPTH); + if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0) + goto disable_fifo; + + wcnt = t->len / bytes_per_word; + if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT) + goto disable_fifo; + + xferlevel = wcnt << 16; + if (t->rx_buf != NULL) { + chconf |= OMAP2_MCSPI_CHCONF_FFER; + xferlevel |= (fifo_depth - 1) << 8; + } else { + chconf |= OMAP2_MCSPI_CHCONF_FFET; + xferlevel |= fifo_depth - 1; + } + + mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel); + mcspi_write_chconf0(spi, chconf); + mcspi->fifo_depth = fifo_depth; + + return; + } + +disable_fifo: + if (t->rx_buf != NULL) + chconf &= ~OMAP2_MCSPI_CHCONF_FFER; + else + chconf &= ~OMAP2_MCSPI_CHCONF_FFET; + + mcspi_write_chconf0(spi, chconf); + mcspi->fifo_depth = 0; +} + static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi) { struct spi_master *spi_cntrl = mcspi->master; @@ -364,7 +437,7 @@ omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, { struct omap2_mcspi *mcspi; struct omap2_mcspi_dma *mcspi_dma; - unsigned int count; + unsigned int count, dma_count; u32 l; int elements = 0; int word_len, element_count; @@ -372,6 +445,11 @@ omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, mcspi = spi_master_get_devdata(spi->master); mcspi_dma = &mcspi->dma_channels[spi->chip_select]; count = xfer->len; + dma_count = xfer->len; + + if (mcspi->fifo_depth == 0) + dma_count -= es; + word_len = cs->word_len; l = mcspi_cached_chconf0(spi); @@ -385,16 +463,15 @@ omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, if (mcspi_dma->dma_rx) { struct dma_async_tx_descriptor *tx; struct scatterlist sg; - size_t len = xfer->len - es; dmaengine_slave_config(mcspi_dma->dma_rx, &cfg); - if (l & OMAP2_MCSPI_CHCONF_TURBO) - len -= es; + if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0) + dma_count -= es; sg_init_table(&sg, 1); sg_dma_address(&sg) = xfer->rx_dma; - sg_dma_len(&sg) = len; + sg_dma_len(&sg) = dma_count; tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | @@ -414,6 +491,10 @@ omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, wait_for_completion(&mcspi_dma->dma_rx_completion); dma_unmap_single(mcspi->dev, xfer->rx_dma, count, DMA_FROM_DEVICE); + + if (mcspi->fifo_depth > 0) + return count; + omap2_mcspi_set_enable(spi, 0); elements = element_count - 1; @@ -433,10 +514,9 @@ omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, else /* word_len <= 32 */ ((u32 *)xfer->rx_buf)[elements++] = w; } else { + int bytes_per_word = mcspi_bytes_per_word(word_len); dev_err(&spi->dev, "DMA RX penultimate word empty"); - count -= (word_len <= 8) ? 2 : - (word_len <= 16) ? 4 : - /* word_len <= 32 */ 8; + count -= (bytes_per_word << 1); omap2_mcspi_set_enable(spi, 1); return count; } @@ -454,9 +534,7 @@ omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, ((u32 *)xfer->rx_buf)[elements] = w; } else { dev_err(&spi->dev, "DMA RX last word empty"); - count -= (word_len <= 8) ? 1 : - (word_len <= 16) ? 2 : - /* word_len <= 32 */ 4; + count -= mcspi_bytes_per_word(word_len); } omap2_mcspi_set_enable(spi, 1); return count; @@ -475,7 +553,10 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) struct dma_slave_config cfg; enum dma_slave_buswidth width; unsigned es; + u32 burst; void __iomem *chstat_reg; + void __iomem *irqstat_reg; + int wait_res; mcspi = spi_master_get_devdata(spi->master); mcspi_dma = &mcspi->dma_channels[spi->chip_select]; @@ -493,19 +574,27 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) es = 4; } + count = xfer->len; + burst = 1; + + if (mcspi->fifo_depth > 0) { + if (count > mcspi->fifo_depth) + burst = mcspi->fifo_depth / es; + else + burst = count / es; + } + memset(&cfg, 0, sizeof(cfg)); cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0; cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0; cfg.src_addr_width = width; cfg.dst_addr_width = width; - cfg.src_maxburst = 1; - cfg.dst_maxburst = 1; + cfg.src_maxburst = burst; + cfg.dst_maxburst = burst; rx = xfer->rx_buf; tx = xfer->tx_buf; - count = xfer->len; - if (tx != NULL) omap2_mcspi_tx_dma(spi, xfer, cfg); @@ -513,18 +602,38 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) count = omap2_mcspi_rx_dma(spi, xfer, cfg, es); if (tx != NULL) { - chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0; wait_for_completion(&mcspi_dma->dma_tx_completion); dma_unmap_single(mcspi->dev, xfer->tx_dma, xfer->len, DMA_TO_DEVICE); + if (mcspi->fifo_depth > 0) { + irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS; + + if (mcspi_wait_for_reg_bit(irqstat_reg, + OMAP2_MCSPI_IRQSTATUS_EOW) < 0) + dev_err(&spi->dev, "EOW timed out\n"); + + mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS, + OMAP2_MCSPI_IRQSTATUS_EOW); + } + /* for TX_ONLY mode, be sure all words have shifted out */ if (rx == NULL) { - if (mcspi_wait_for_reg_bit(chstat_reg, - OMAP2_MCSPI_CHSTAT_TXS) < 0) - dev_err(&spi->dev, "TXS timed out\n"); - else if (mcspi_wait_for_reg_bit(chstat_reg, - OMAP2_MCSPI_CHSTAT_EOT) < 0) + chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0; + if (mcspi->fifo_depth > 0) { + wait_res = mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_TXFFE); + if (wait_res < 0) + dev_err(&spi->dev, "TXFFE timed out\n"); + } else { + wait_res = mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_TXS); + if (wait_res < 0) + dev_err(&spi->dev, "TXS timed out\n"); + } + if (wait_res >= 0 && + (mcspi_wait_for_reg_bit(chstat_reg, + OMAP2_MCSPI_CHSTAT_EOT) < 0)) dev_err(&spi->dev, "EOT timed out\n"); } } @@ -830,12 +939,20 @@ static int omap2_mcspi_request_dma(struct spi_device *spi) dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); sig = mcspi_dma->dma_rx_sync_dev; - mcspi_dma->dma_rx = dma_request_channel(mask, omap_dma_filter_fn, &sig); + + mcspi_dma->dma_rx = + dma_request_slave_channel_compat(mask, omap_dma_filter_fn, + &sig, &master->dev, + mcspi_dma->dma_rx_ch_name); if (!mcspi_dma->dma_rx) goto no_dma; sig = mcspi_dma->dma_tx_sync_dev; - mcspi_dma->dma_tx = dma_request_channel(mask, omap_dma_filter_fn, &sig); + mcspi_dma->dma_tx = + dma_request_slave_channel_compat(mask, omap_dma_filter_fn, + &sig, &master->dev, + mcspi_dma->dma_tx_ch_name); + if (!mcspi_dma->dma_tx) { dma_release_channel(mcspi_dma->dma_rx); mcspi_dma->dma_rx = NULL; @@ -857,12 +974,6 @@ static int omap2_mcspi_setup(struct spi_device *spi) struct omap2_mcspi_dma *mcspi_dma; struct omap2_mcspi_cs *cs = spi->controller_state; - if (spi->bits_per_word < 4 || spi->bits_per_word > 32) { - dev_dbg(&spi->dev, "setup: unsupported %d bit words\n", - spi->bits_per_word); - return -EINVAL; - } - mcspi_dma = &mcspi->dma_channels[spi->chip_select]; if (!cs) { @@ -951,7 +1062,7 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m) cs = spi->controller_state; cd = spi->controller_data; - omap2_mcspi_set_enable(spi, 1); + omap2_mcspi_set_enable(spi, 0); list_for_each_entry(t, &m->transfers, transfer_list) { if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) { status = -EINVAL; @@ -999,6 +1110,12 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m) if (t->len) { unsigned count; + if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) && + (m->is_dma_mapped || t->len >= DMA_MIN_BYTES)) + omap2_mcspi_set_fifo(spi, t, 1); + + omap2_mcspi_set_enable(spi, 1); + /* RX_ONLY mode needs dummy data in TX reg */ if (t->tx_buf == NULL) __raw_writel(0, cs->base @@ -1025,6 +1142,11 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m) omap2_mcspi_force_cs(spi, 0); cs_active = 0; } + + omap2_mcspi_set_enable(spi, 0); + + if (mcspi->fifo_depth > 0) + omap2_mcspi_set_fifo(spi, t, 0); } /* Restore defaults if they were overriden */ if (par_override) { @@ -1045,8 +1167,10 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m) omap2_mcspi_set_enable(spi, 0); - m->status = status; + if (mcspi->fifo_depth > 0 && t) + omap2_mcspi_set_fifo(spi, t, 0); + m->status = status; } static int omap2_mcspi_transfer_one_message(struct spi_master *master, @@ -1072,10 +1196,7 @@ static int omap2_mcspi_transfer_one_message(struct spi_master *master, unsigned len = t->len; if (t->speed_hz > OMAP2_MCSPI_MAX_FREQ - || (len && !(rx_buf || tx_buf)) - || (t->bits_per_word && - ( t->bits_per_word < 4 - || t->bits_per_word > 32))) { + || (len && !(rx_buf || tx_buf))) { dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n", t->speed_hz, len, @@ -1186,7 +1307,6 @@ static int omap2_mcspi_probe(struct platform_device *pdev) static int bus_num = 1; struct device_node *node = pdev->dev.of_node; const struct of_device_id *match; - struct pinctrl *pinctrl; master = spi_alloc_master(&pdev->dev, sizeof *mcspi); if (master == NULL) { @@ -1196,7 +1316,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev) /* the spi->mode bits understood by this driver: */ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; - + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); master->setup = omap2_mcspi_setup; master->prepare_transfer_hardware = omap2_prepare_transfer; master->unprepare_transfer_hardware = omap2_unprepare_transfer; @@ -1256,39 +1376,47 @@ static int omap2_mcspi_probe(struct platform_device *pdev) goto free_master; for (i = 0; i < master->num_chipselect; i++) { - char dma_ch_name[14]; + char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name; + char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name; struct resource *dma_res; - sprintf(dma_ch_name, "rx%d", i); - dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA, - dma_ch_name); - if (!dma_res) { - dev_dbg(&pdev->dev, "cannot get DMA RX channel\n"); - status = -ENODEV; - break; - } + sprintf(dma_rx_ch_name, "rx%d", i); + if (!pdev->dev.of_node) { + dma_res = + platform_get_resource_byname(pdev, + IORESOURCE_DMA, + dma_rx_ch_name); + if (!dma_res) { + dev_dbg(&pdev->dev, + "cannot get DMA RX channel\n"); + status = -ENODEV; + break; + } - mcspi->dma_channels[i].dma_rx_sync_dev = dma_res->start; - sprintf(dma_ch_name, "tx%d", i); - dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA, - dma_ch_name); - if (!dma_res) { - dev_dbg(&pdev->dev, "cannot get DMA TX channel\n"); - status = -ENODEV; - break; + mcspi->dma_channels[i].dma_rx_sync_dev = + dma_res->start; } + sprintf(dma_tx_ch_name, "tx%d", i); + if (!pdev->dev.of_node) { + dma_res = + platform_get_resource_byname(pdev, + IORESOURCE_DMA, + dma_tx_ch_name); + if (!dma_res) { + dev_dbg(&pdev->dev, + "cannot get DMA TX channel\n"); + status = -ENODEV; + break; + } - mcspi->dma_channels[i].dma_tx_sync_dev = dma_res->start; + mcspi->dma_channels[i].dma_tx_sync_dev = + dma_res->start; + } } if (status < 0) goto dma_chnl_free; - pinctrl = devm_pinctrl_get_select_default(&pdev->dev); - if (IS_ERR(pinctrl)) - dev_warn(&pdev->dev, - "pins are not configured from the driver\n"); - pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT); pm_runtime_enable(&pdev->dev); |