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Merge remote-tracking branch 'spi/topic/omap' into spi-next

Mark Brown 12 years ago
parent
commit
1728ddb2ca
2 changed files with 213 additions and 51 deletions
  1. 26 1
      Documentation/devicetree/bindings/spi/omap-spi.txt
  2. 187 50
      drivers/spi/spi-omap2-mcspi.c

+ 26 - 1
Documentation/devicetree/bindings/spi/omap-spi.txt

@@ -10,7 +10,18 @@ Required properties:
 			  input. The default is D0 as input and
 			  D1 as output.
 
-Example:
+Optional properties:
+- dmas: List of DMA specifiers with the controller specific format
+	as described in the generic DMA client binding. A tx and rx
+	specifier is required for each chip select.
+- dma-names: List of DMA request names. These strings correspond
+	1:1 with the DMA specifiers listed in dmas. The string naming
+	is to be "rxN" and "txN" for RX and TX requests,
+	respectively, where N equals the chip select number.
+
+Examples:
+
+[hwmod populated DMA resources]
 
 mcspi1: mcspi@1 {
     #address-cells = <1>;
@@ -20,3 +31,17 @@ mcspi1: mcspi@1 {
     ti,spi-num-cs = <4>;
 };
 
+[generic DMA request binding]
+
+mcspi1: mcspi@1 {
+    #address-cells = <1>;
+    #size-cells = <0>;
+    compatible = "ti,omap4-mcspi";
+    ti,hwmods = "mcspi1";
+    ti,spi-num-cs = <2>;
+    dmas = <&edma 42
+	    &edma 43
+	    &edma 44
+	    &edma 45>;
+    dma-names = "tx0", "rx0", "tx1", "rx1";
+};

+ 187 - 50
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;
@@ -945,7 +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;
@@ -993,6 +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
@@ -1019,6 +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) {
@@ -1039,8 +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,
@@ -1177,7 +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) {
@@ -1247,39 +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);