dm: sf: sandbox: Convert SPI flash driver to driver model

Convert sandbox's spi flash emulation driver to use driver model.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>

arch/sandbox/include/asm/spi.h

@@ -33,19 +33,6 @@ struct sandbox_spi_emu_ops {
 };
 
 /*
- * There are times when the data lines are allowed to tristate.  What
- * is actually sensed on the line depends on the hardware.  It could
- * always be 0xFF/0x00 (if there are pull ups/downs), or things could
- * float and so we'd get garbage back.  This func encapsulates that
- * scenario so we can worry about the details here.
- */
-static inline void sandbox_spi_tristate(u8 *buf, uint len)
-{
-	/* XXX: make this into a user config option ? */
-	memset(buf, 0xff, len);
-}
-
-/*
  * Extract the bus/cs from the spi spec and return the start of the spi
  * client spec.  If the bus/cs are invalid for the current config, then
  * it returns NULL.

arch/sandbox/include/asm/state.h

@@ -42,7 +42,6 @@ enum state_terminal_raw {
 
 struct sandbox_spi_info {
 	const char *spec;
-	const struct sandbox_spi_emu_ops *ops;
 	struct udevice *emul;
 };
 

drivers/mtd/spi/sandbox.c

@@ -9,6 +9,7 @@
  */
 
 #include <common.h>
+#include <dm.h>
 #include <malloc.h>
 #include <spi.h>
 #include <os.h>
@@ -19,6 +20,11 @@
 #include <asm/getopt.h>
 #include <asm/spi.h>
 #include <asm/state.h>
+#include <dm/device-internal.h>
+#include <dm/lists.h>
+#include <dm/uclass-internal.h>
+
+DECLARE_GLOBAL_DATA_PTR;
 
 /*
  * The different states that our SPI flash transitions between.
@@ -34,12 +40,14 @@ enum sandbox_sf_state {
 	SF_ERASE, /* erase the flash */
 	SF_READ_STATUS, /* read the flash's status register */
 	SF_READ_STATUS1, /* read the flash's status register upper 8 bits*/
+	SF_WRITE_STATUS, /* write the flash's status register */
 };
 
 static const char *sandbox_sf_state_name(enum sandbox_sf_state state)
 {
 	static const char * const states[] = {
 		"CMD", "ID", "ADDR", "READ", "WRITE", "ERASE", "READ_STATUS",
+		"READ_STATUS1", "WRITE_STATUS",
 	};
 	return states[state];
 }
@@ -58,6 +66,7 @@ static u8 sandbox_sf_0xff[0x1000];
 
 /* Internal state data for each SPI flash */
 struct sandbox_spi_flash {
+	unsigned int cs;	/* Chip select we are attached to */
 	/*
 	 * As we receive data over the SPI bus, our flash transitions
 	 * between states.  For example, we start off in the SF_CMD
@@ -84,71 +93,124 @@ struct sandbox_spi_flash {
 	int fd;
 };
 
-static int sandbox_sf_setup(void **priv, const char *spec)
+struct sandbox_spi_flash_plat_data {
+	const char *filename;
+	const char *device_name;
+	int bus;
+	int cs;
+};
+
+/**
+ * This is a very strange probe function. If it has platform data (which may
+ * have come from the device tree) then this function gets the filename and
+ * device type from there. Failing that it looks at the command line
+ * parameter.
+ */
+static int sandbox_sf_probe(struct udevice *dev)
 {
 	/* spec = idcode:file */
-	struct sandbox_spi_flash *sbsf;
+	struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
 	const char *file;
 	size_t len, idname_len;
 	const struct spi_flash_params *data;
-
-	file = strchr(spec, ':');
-	if (!file) {
-		printf("sandbox_sf: unable to parse file\n");
-		goto error;
+	struct sandbox_spi_flash_plat_data *pdata = dev_get_platdata(dev);
+	struct sandbox_state *state = state_get_current();
+	struct udevice *bus = dev->parent;
+	const char *spec = NULL;
+	int ret = 0;
+	int cs = -1;
+	int i;
+
+	debug("%s: bus %d, looking for emul=%p: ", __func__, bus->seq, dev);
+	if (bus->seq >= 0 && bus->seq < CONFIG_SANDBOX_SPI_MAX_BUS) {
+		for (i = 0; i < CONFIG_SANDBOX_SPI_MAX_CS; i++) {
+			if (state->spi[bus->seq][i].emul == dev)
+				cs = i;
+		}
+	}
+	if (cs == -1) {
+		printf("Error: Unknown chip select for device '%s'",
+		       dev->name);
+		return -EINVAL;
+	}
+	debug("found at cs %d\n", cs);
+
+	if (!pdata->filename) {
+		struct sandbox_state *state = state_get_current();
+
+		assert(bus->seq != -1);
+		if (bus->seq < CONFIG_SANDBOX_SPI_MAX_BUS)
+			spec = state->spi[bus->seq][cs].spec;
+		if (!spec)
+			return -ENOENT;
+
+		file = strchr(spec, ':');
+		if (!file) {
+			printf("sandbox_sf: unable to parse file\n");
+			ret = -EINVAL;
+			goto error;
+		}
+		idname_len = file - spec;
+		pdata->filename = file + 1;
+		pdata->device_name = spec;
+		++file;
+	} else {
+		spec = strchr(pdata->device_name, ',');
+		if (spec)
+			spec++;
+		else
+			spec = pdata->device_name;
+		idname_len = strlen(spec);
 	}
-	idname_len = file - spec;
-	++file;
+	debug("%s: device='%s'\n", __func__, spec);
 
 	for (data = spi_flash_params_table; data->name; data++) {
 		len = strlen(data->name);
 		if (idname_len != len)
 			continue;
-		if (!memcmp(spec, data->name, len))
+		if (!strncasecmp(spec, data->name, len))
 			break;
 	}
 	if (!data->name) {
 		printf("sandbox_sf: unknown flash '%*s'\n", (int)idname_len,
 		       spec);
+		ret = -EINVAL;
 		goto error;
 	}
 
 	if (sandbox_sf_0xff[0] == 0x00)
 		memset(sandbox_sf_0xff, 0xff, sizeof(sandbox_sf_0xff));
 
-	sbsf = calloc(sizeof(*sbsf), 1);
-	if (!sbsf) {
-		printf("sandbox_sf: out of memory\n");
-		goto error;
-	}
-
-	sbsf->fd = os_open(file, 02);
+	sbsf->fd = os_open(pdata->filename, 02);
 	if (sbsf->fd == -1) {
 		free(sbsf);
-		printf("sandbox_sf: unable to open file '%s'\n", file);
+		printf("sandbox_sf: unable to open file '%s'\n",
+		       pdata->filename);
+		ret = -EIO;
 		goto error;
 	}
 
 	sbsf->data = data;
+	sbsf->cs = cs;
 
-	*priv = sbsf;
 	return 0;
 
  error:
-	return 1;
+	return ret;
 }
 
-static void sandbox_sf_free(void *priv)
+static int sandbox_sf_remove(struct udevice *dev)
 {
-	struct sandbox_spi_flash *sbsf = priv;
+	struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
 
 	os_close(sbsf->fd);
-	free(sbsf);
+
+	return 0;
 }
 
-static void sandbox_sf_cs_activate(void *priv)
+static void sandbox_sf_cs_activate(struct udevice *dev)
 {
-	struct sandbox_spi_flash *sbsf = priv;
+	struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
 
 	debug("sandbox_sf: CS activated; state is fresh!\n");
 
@@ -160,11 +222,24 @@ static void sandbox_sf_cs_activate(void *priv)
 	sbsf->cmd = SF_CMD;
 }
 
-static void sandbox_sf_cs_deactivate(void *priv)
+static void sandbox_sf_cs_deactivate(struct udevice *dev)
 {
 	debug("sandbox_sf: CS deactivated; cmd done processing!\n");
 }
 
+/*
+ * There are times when the data lines are allowed to tristate.  What
+ * is actually sensed on the line depends on the hardware.  It could
+ * always be 0xFF/0x00 (if there are pull ups/downs), or things could
+ * float and so we'd get garbage back.  This func encapsulates that
+ * scenario so we can worry about the details here.
+ */
+static void sandbox_spi_tristate(u8 *buf, uint len)
+{
+	/* XXX: make this into a user config option ? */
+	memset(buf, 0xff, len);
+}
+
 /* Figure out what command this stream is telling us to do */
 static int sandbox_sf_process_cmd(struct sandbox_spi_flash *sbsf, const u8 *rx,
 				  u8 *tx)
@@ -172,7 +247,8 @@ static int sandbox_sf_process_cmd(struct sandbox_spi_flash *sbsf, const u8 *rx,
 	enum sandbox_sf_state oldstate = sbsf->state;
 
 	/* We need to output a byte for the cmd byte we just ate */
-	sandbox_spi_tristate(tx, 1);
+	if (tx)
+		sandbox_spi_tristate(tx, 1);
 
 	sbsf->cmd = rx[0];
 	switch (sbsf->cmd) {
@@ -200,6 +276,9 @@ static int sandbox_sf_process_cmd(struct sandbox_spi_flash *sbsf, const u8 *rx,
 		debug(" write enabled\n");
 		sbsf->status |= STAT_WEL;
 		break;
+	case CMD_WRITE_STATUS:
+		sbsf->state = SF_WRITE_STATUS;
+		break;
 	default: {
 		int flags = sbsf->data->flags;
 
@@ -216,7 +295,7 @@ static int sandbox_sf_process_cmd(struct sandbox_spi_flash *sbsf, const u8 *rx,
 			sbsf->erase_size = 64 << 10;
 		} else {
 			debug(" cmd unknown: %#x\n", sbsf->cmd);
-			return 1;
+			return -EIO;
 		}
 		sbsf->state = SF_ADDR;
 		break;
@@ -246,20 +325,27 @@ int sandbox_erase_part(struct sandbox_spi_flash *sbsf, int size)
 	return 0;
 }
 
-static int sandbox_sf_xfer(void *priv, const u8 *rx, u8 *tx,
-		uint bytes)
+static int sandbox_sf_xfer(struct udevice *dev, unsigned int bitlen,
+			   const void *rxp, void *txp, unsigned long flags)
 {
-	struct sandbox_spi_flash *sbsf = priv;
+	struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
+	const uint8_t *rx = rxp;
+	uint8_t *tx = txp;
 	uint cnt, pos = 0;
+	int bytes = bitlen / 8;
 	int ret;
 
 	debug("sandbox_sf: state:%x(%s) bytes:%u\n", sbsf->state,
 	      sandbox_sf_state_name(sbsf->state), bytes);
 
+	if ((flags & SPI_XFER_BEGIN))
+		sandbox_sf_cs_activate(dev);
+
 	if (sbsf->state == SF_CMD) {
 		/* Figure out the initial state */
-		if (sandbox_sf_process_cmd(sbsf, rx, tx))
-			return 1;
+		ret = sandbox_sf_process_cmd(sbsf, rx, tx);
+		if (ret)
+			return ret;
 		++pos;
 	}
 
@@ -290,7 +376,9 @@ static int sandbox_sf_xfer(void *priv, const u8 *rx, u8 *tx,
 				sbsf->off = (sbsf->off << 8) | rx[pos];
 			debug("addr:%06x\n", sbsf->off);
 
-			sandbox_spi_tristate(&tx[pos++], 1);
+			if (tx)
+				sandbox_spi_tristate(&tx[pos], 1);
+			pos++;
 
 			/* See if we're done processing */
 			if (sbsf->addr_bytes <
@@ -300,7 +388,7 @@ static int sandbox_sf_xfer(void *priv, const u8 *rx, u8 *tx,
 			/* Next state! */
 			if (os_lseek(sbsf->fd, sbsf->off, OS_SEEK_SET) < 0) {
 				puts("sandbox_sf: os_lseek() failed");
-				return 1;
+				return -EIO;
 			}
 			switch (sbsf->cmd) {
 			case CMD_READ_ARRAY_FAST:
@@ -326,10 +414,11 @@ static int sandbox_sf_xfer(void *priv, const u8 *rx, u8 *tx,
 
 			cnt = bytes - pos;
 			debug(" tx: read(%u)\n", cnt);
+			assert(tx);
 			ret = os_read(sbsf->fd, tx + pos, cnt);
 			if (ret < 0) {
-				puts("sandbox_spi: os_read() failed\n");
-				return 1;
+				puts("sandbox_sf: os_read() failed\n");
+				return -EIO;
 			}
 			pos += ret;
 			break;
@@ -345,6 +434,10 @@ static int sandbox_sf_xfer(void *priv, const u8 *rx, u8 *tx,
 			memset(tx + pos, sbsf->status >> 8, cnt);
 			pos += cnt;
 			break;
+		case SF_WRITE_STATUS:
+			debug(" write status: %#x (ignored)\n", rx[pos]);
+			pos = bytes;
+			break;
 		case SF_WRITE:
 			/*
 			 * XXX: need to handle exotic behavior:
@@ -359,11 +452,12 @@ static int sandbox_sf_xfer(void *priv, const u8 *rx, u8 *tx,
 
 			cnt = bytes - pos;
 			debug(" rx: write(%u)\n", cnt);
-			sandbox_spi_tristate(&tx[pos], cnt);
+			if (tx)
+				sandbox_spi_tristate(&tx[pos], cnt);
 			ret = os_write(sbsf->fd, rx + pos, cnt);
 			if (ret < 0) {
 				puts("sandbox_spi: os_write() failed\n");
-				return 1;
+				return -EIO;
 			}
 			pos += ret;
 			sbsf->status &= ~STAT_WEL;
@@ -388,7 +482,8 @@ static int sandbox_sf_xfer(void *priv, const u8 *rx, u8 *tx,
 			      sbsf->erase_size);
 
 			cnt = bytes - pos;
-			sandbox_spi_tristate(&tx[pos], cnt);
+			if (tx)
+				sandbox_spi_tristate(&tx[pos], cnt);
 			pos += cnt;
 
 			/*
@@ -410,17 +505,33 @@ static int sandbox_sf_xfer(void *priv, const u8 *rx, u8 *tx,
 	}
 
  done:
-	return pos == bytes ? 0 : 1;
+	if (flags & SPI_XFER_END)
+		sandbox_sf_cs_deactivate(dev);
+	return pos == bytes ? 0 : -EIO;
+}
+
+int sandbox_sf_ofdata_to_platdata(struct udevice *dev)
+{
+	struct sandbox_spi_flash_plat_data *pdata = dev_get_platdata(dev);
+	const void *blob = gd->fdt_blob;
+	int node = dev->of_offset;
+
+	pdata->filename = fdt_getprop(blob, node, "sandbox,filename", NULL);
+	pdata->device_name = fdt_getprop(blob, node, "compatible", NULL);
+	if (!pdata->filename || !pdata->device_name) {
+		debug("%s: Missing properties, filename=%s, device_name=%s\n",
+		      __func__, pdata->filename, pdata->device_name);
+		return -EINVAL;
+	}
+
+	return 0;
 }
 
-static const struct sandbox_spi_emu_ops sandbox_sf_ops = {
-	.setup         = sandbox_sf_setup,
-	.free          = sandbox_sf_free,
-	.cs_activate   = sandbox_sf_cs_activate,
-	.cs_deactivate = sandbox_sf_cs_deactivate,
+static const struct dm_spi_emul_ops sandbox_sf_emul_ops = {
 	.xfer          = sandbox_sf_xfer,
 };
 
+#ifdef CONFIG_SPI_FLASH
 static int sandbox_cmdline_cb_spi_sf(struct sandbox_state *state,
 				     const char *arg)
 {
@@ -438,8 +549,141 @@ static int sandbox_cmdline_cb_spi_sf(struct sandbox_state *state,
 	 * spec here, but the problem is that no U-Boot init has been done
 	 * yet. Perhaps we can figure something out.
 	 */
-	state->spi[bus][cs].ops = &sandbox_sf_ops;
 	state->spi[bus][cs].spec = spec;
 	return 0;
 }
 SANDBOX_CMDLINE_OPT(spi_sf, 1, "connect a SPI flash: <bus>:<cs>:<id>:<file>");
+
+int sandbox_sf_bind_emul(struct sandbox_state *state, int busnum, int cs,
+			 struct udevice *bus, int of_offset, const char *spec)
+{
+	struct udevice *emul;
+	char name[20], *str;
+	struct driver *drv;
+	int ret;
+
+	/* now the emulator */
+	strncpy(name, spec, sizeof(name) - 6);
+	name[sizeof(name) - 6] = '\0';
+	strcat(name, "-emul");
+	str = strdup(name);
+	if (!str)
+		return -ENOMEM;
+	drv = lists_driver_lookup_name("sandbox_sf_emul");
+	if (!drv) {
+		puts("Cannot find sandbox_sf_emul driver\n");
+		return -ENOENT;
+	}
+	ret = device_bind(bus, drv, str, NULL, of_offset, &emul);
+	if (ret) {
+		printf("Cannot create emul device for spec '%s' (err=%d)\n",
+		       spec, ret);
+		return ret;
+	}
+	state->spi[busnum][cs].emul = emul;
+
+	return 0;
+}
+
+void sandbox_sf_unbind_emul(struct sandbox_state *state, int busnum, int cs)
+{
+	state->spi[busnum][cs].emul = NULL;
+}
+
+static int sandbox_sf_bind_bus_cs(struct sandbox_state *state, int busnum,
+				  int cs, const char *spec)
+{
+	struct udevice *bus, *slave;
+	int ret;
+
+	ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, true, &bus);
+	if (ret) {
+		printf("Invalid bus %d for spec '%s' (err=%d)\n", busnum,
+		       spec, ret);
+		return ret;
+	}
+	ret = device_find_child_by_seq(bus, cs, true, &slave);
+	if (!ret) {
+		printf("Chip select %d already exists for spec '%s'\n", cs,
+		       spec);
+		return -EEXIST;
+	}
+
+	ret = spi_bind_device(bus, cs, "spi_flash_std", spec, &slave);
+	if (ret)
+		return ret;
+
+	return sandbox_sf_bind_emul(state, busnum, cs, bus, -1, spec);
+}
+
+int sandbox_spi_get_emul(struct sandbox_state *state,
+			 struct udevice *bus, struct udevice *slave,
+			 struct udevice **emulp)
+{
+	struct sandbox_spi_info *info;
+	int busnum = bus->seq;
+	int cs = spi_chip_select(slave);
+	int ret;
+
+	info = &state->spi[busnum][cs];
+	if (!info->emul) {
+		/* Use the same device tree node as the SPI flash device */
+		debug("%s: busnum=%u, cs=%u: binding SPI flash emulation: ",
+		      __func__, busnum, cs);
+		ret = sandbox_sf_bind_emul(state, busnum, cs, bus,
+					   slave->of_offset, slave->name);
+		if (ret) {
+			debug("failed (err=%d)\n", ret);
+			return ret;
+		}
+		debug("OK\n");
+	}
+	*emulp = info->emul;
+
+	return 0;
+}
+
+int dm_scan_other(bool pre_reloc_only)
+{
+	struct sandbox_state *state = state_get_current();
+	int busnum, cs;
+
+	if (pre_reloc_only)
+		return 0;
+	for (busnum = 0; busnum < CONFIG_SANDBOX_SPI_MAX_BUS; busnum++) {
+		for (cs = 0; cs < CONFIG_SANDBOX_SPI_MAX_CS; cs++) {
+			const char *spec = state->spi[busnum][cs].spec;
+			int ret;
+
+			if (spec) {
+				ret = sandbox_sf_bind_bus_cs(state, busnum,
+							     cs, spec);
+				if (ret) {
+					debug("%s: Bind failed for bus %d, cs %d\n",
+					      __func__, busnum, cs);
+					return ret;
+				}
+			}
+		}
+	}
+
+	return 0;
+}
+#endif
+
+static const struct udevice_id sandbox_sf_ids[] = {
+	{ .compatible = "sandbox,spi-flash" },
+	{ }
+};
+
+U_BOOT_DRIVER(sandbox_sf_emul) = {
+	.name		= "sandbox_sf_emul",
+	.id		= UCLASS_SPI_EMUL,
+	.of_match	= sandbox_sf_ids,
+	.ofdata_to_platdata = sandbox_sf_ofdata_to_platdata,
+	.probe		= sandbox_sf_probe,
+	.remove		= sandbox_sf_remove,
+	.priv_auto_alloc_size = sizeof(struct sandbox_spi_flash),
+	.platdata_auto_alloc_size = sizeof(struct sandbox_spi_flash_plat_data),
+	.ops		= &sandbox_sf_emul_ops,
+};

include/configs/sandbox.h

@@ -98,6 +98,7 @@
 #define CONFIG_CMD_SPI
 #define CONFIG_SPI_FLASH
 #define CONFIG_DM_SPI
+#define CONFIG_DM_SPI_FLASH
 #define CONFIG_SPI_FLASH_ATMEL
 #define CONFIG_SPI_FLASH_EON
 #define CONFIG_SPI_FLASH_GIGADEVICE