1 files changed, 266 insertions, 177 deletions

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 028514c6996f..d3f8a78efd3b 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -7,16 +7,18 @@
  * Copyright (C) 2014, Freescale Semiconductor, Inc.
  */
 
-#include <linux/err.h>
-#include <linux/errno.h>
+#include <linux/cleanup.h>
 #include <linux/delay.h>
 #include <linux/device.h>
+#include <linux/err.h>
+#include <linux/errno.h>
 #include <linux/math64.h>
 #include <linux/module.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/spi-nor.h>
 #include <linux/mutex.h>
-#include <linux/of_platform.h>
+#include <linux/of.h>
+#include <linux/regulator/consumer.h>
 #include <linux/sched/task_stack.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
@@ -113,6 +115,9 @@ void spi_nor_spimem_setup_op(const struct spi_nor *nor,
 		op->cmd.opcode = (op->cmd.opcode << 8) | ext;
 		op->cmd.nbytes = 2;
 	}
+
+	if (proto == SNOR_PROTO_8_8_8_DTR && nor->flags & SNOR_F_SWAP16)
+		op->data.swap16 = true;
 }
 
 /**
@@ -635,32 +640,26 @@ static bool spi_nor_use_parallel_locking(struct spi_nor *nor)
 static int spi_nor_rww_start_rdst(struct spi_nor *nor)
 {
 	struct spi_nor_rww *rww = &nor->rww;
-	int ret = -EAGAIN;
 
-	mutex_lock(&nor->lock);
+	guard(mutex)(&nor->lock);
 
 	if (rww->ongoing_io || rww->ongoing_rd)
-		goto busy;
+		return -EAGAIN;
 
 	rww->ongoing_io = true;
 	rww->ongoing_rd = true;
-	ret = 0;
 
-busy:
-	mutex_unlock(&nor->lock);
-	return ret;
+	return 0;
 }
 
 static void spi_nor_rww_end_rdst(struct spi_nor *nor)
 {
 	struct spi_nor_rww *rww = &nor->rww;
 
-	mutex_lock(&nor->lock);
+	guard(mutex)(&nor->lock);
 
 	rww->ongoing_io = false;
 	rww->ongoing_rd = false;
-
-	mutex_unlock(&nor->lock);
 }
 
 static int spi_nor_lock_rdst(struct spi_nor *nor)
@@ -1208,26 +1207,21 @@ static void spi_nor_offset_to_banks(u64 bank_size, loff_t start, size_t len,
 static bool spi_nor_rww_start_io(struct spi_nor *nor)
 {
 	struct spi_nor_rww *rww = &nor->rww;
-	bool start = false;
 
-	mutex_lock(&nor->lock);
+	guard(mutex)(&nor->lock);
 
 	if (rww->ongoing_io)
-		goto busy;
+		return false;
 
 	rww->ongoing_io = true;
-	start = true;
 
-busy:
-	mutex_unlock(&nor->lock);
-	return start;
+	return true;
 }
 
 static void spi_nor_rww_end_io(struct spi_nor *nor)
 {
-	mutex_lock(&nor->lock);
+	guard(mutex)(&nor->lock);
 	nor->rww.ongoing_io = false;
-	mutex_unlock(&nor->lock);
 }
 
 static int spi_nor_lock_device(struct spi_nor *nor)
@@ -1250,32 +1244,27 @@ static void spi_nor_unlock_device(struct spi_nor *nor)
 static bool spi_nor_rww_start_exclusive(struct spi_nor *nor)
 {
 	struct spi_nor_rww *rww = &nor->rww;
-	bool start = false;
 
 	mutex_lock(&nor->lock);
 
 	if (rww->ongoing_io || rww->ongoing_rd || rww->ongoing_pe)
-		goto busy;
+		return false;
 
 	rww->ongoing_io = true;
 	rww->ongoing_rd = true;
 	rww->ongoing_pe = true;
-	start = true;
 
-busy:
-	mutex_unlock(&nor->lock);
-	return start;
+	return true;
 }
 
 static void spi_nor_rww_end_exclusive(struct spi_nor *nor)
 {
 	struct spi_nor_rww *rww = &nor->rww;
 
-	mutex_lock(&nor->lock);
+	guard(mutex)(&nor->lock);
 	rww->ongoing_io = false;
 	rww->ongoing_rd = false;
 	rww->ongoing_pe = false;
-	mutex_unlock(&nor->lock);
 }
 
 int spi_nor_prep_and_lock(struct spi_nor *nor)
@@ -1312,30 +1301,26 @@ static bool spi_nor_rww_start_pe(struct spi_nor *nor, loff_t start, size_t len)
 {
 	struct spi_nor_rww *rww = &nor->rww;
 	unsigned int used_banks = 0;
-	bool started = false;
 	u8 first, last;
 	int bank;
 
-	mutex_lock(&nor->lock);
+	guard(mutex)(&nor->lock);
 
 	if (rww->ongoing_io || rww->ongoing_rd || rww->ongoing_pe)
-		goto busy;
+		return false;
 
 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
 	for (bank = first; bank <= last; bank++) {
 		if (rww->used_banks & BIT(bank))
-			goto busy;
+			return false;
 
 		used_banks |= BIT(bank);
 	}
 
 	rww->used_banks |= used_banks;
 	rww->ongoing_pe = true;
-	started = true;
 
-busy:
-	mutex_unlock(&nor->lock);
-	return started;
+	return true;
 }
 
 static void spi_nor_rww_end_pe(struct spi_nor *nor, loff_t start, size_t len)
@@ -1344,15 +1329,13 @@ static void spi_nor_rww_end_pe(struct spi_nor *nor, loff_t start, size_t len)
 	u8 first, last;
 	int bank;
 
-	mutex_lock(&nor->lock);
+	guard(mutex)(&nor->lock);
 
 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
 	for (bank = first; bank <= last; bank++)
 		rww->used_banks &= ~BIT(bank);
 
 	rww->ongoing_pe = false;
-
-	mutex_unlock(&nor->lock);
 }
 
 static int spi_nor_prep_and_lock_pe(struct spi_nor *nor, loff_t start, size_t len)
@@ -1389,19 +1372,18 @@ static bool spi_nor_rww_start_rd(struct spi_nor *nor, loff_t start, size_t len)
 {
 	struct spi_nor_rww *rww = &nor->rww;
 	unsigned int used_banks = 0;
-	bool started = false;
 	u8 first, last;
 	int bank;
 
-	mutex_lock(&nor->lock);
+	guard(mutex)(&nor->lock);
 
 	if (rww->ongoing_io || rww->ongoing_rd)
-		goto busy;
+		return false;
 
 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
 	for (bank = first; bank <= last; bank++) {
 		if (rww->used_banks & BIT(bank))
-			goto busy;
+			return false;
 
 		used_banks |= BIT(bank);
 	}
@@ -1409,11 +1391,8 @@ static bool spi_nor_rww_start_rd(struct spi_nor *nor, loff_t start, size_t len)
 	rww->used_banks |= used_banks;
 	rww->ongoing_io = true;
 	rww->ongoing_rd = true;
-	started = true;
 
-busy:
-	mutex_unlock(&nor->lock);
-	return started;
+	return true;
 }
 
 static void spi_nor_rww_end_rd(struct spi_nor *nor, loff_t start, size_t len)
@@ -1422,7 +1401,7 @@ static void spi_nor_rww_end_rd(struct spi_nor *nor, loff_t start, size_t len)
 	u8 first, last;
 	int bank;
 
-	mutex_lock(&nor->lock);
+	guard(mutex)(&nor->lock);
 
 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
 	for (bank = first; bank <= last; bank++)
@@ -1430,8 +1409,6 @@ static void spi_nor_rww_end_rd(struct spi_nor *nor, loff_t start, size_t len)
 
 	rww->ongoing_io = false;
 	rww->ongoing_rd = false;
-
-	mutex_unlock(&nor->lock);
 }
 
 static int spi_nor_prep_and_lock_rd(struct spi_nor *nor, loff_t start, size_t len)
@@ -1463,14 +1440,6 @@ static void spi_nor_unlock_and_unprep_rd(struct spi_nor *nor, loff_t start, size
 	spi_nor_unprep(nor);
 }
 
-static u32 spi_nor_convert_addr(struct spi_nor *nor, loff_t addr)
-{
-	if (!nor->params->convert_addr)
-		return addr;
-
-	return nor->params->convert_addr(nor, addr);
-}
-
 /*
  * Initiate the erasure of a single sector
  */
@@ -1478,8 +1447,6 @@ int spi_nor_erase_sector(struct spi_nor *nor, u32 addr)
 {
 	int i;
 
-	addr = spi_nor_convert_addr(nor, addr);
-
 	if (nor->spimem) {
 		struct spi_mem_op op =
 			SPI_NOR_SECTOR_ERASE_OP(nor->erase_opcode,
@@ -1986,7 +1953,6 @@ static const struct spi_nor_manufacturer *manufacturers[] = {
 	&spi_nor_spansion,
 	&spi_nor_sst,
 	&spi_nor_winbond,
-	&spi_nor_xilinx,
 	&spi_nor_xmc,
 };
 
@@ -2048,6 +2014,76 @@ static const struct flash_info *spi_nor_detect(struct spi_nor *nor)
 	return info;
 }
 
+/*
+ * On Octal DTR capable flashes, reads cannot start or end at an odd
+ * address in Octal DTR mode. Extra bytes need to be read at the start
+ * or end to make sure both the start address and length remain even.
+ */
+static int spi_nor_octal_dtr_read(struct spi_nor *nor, loff_t from, size_t len,
+				  u_char *buf)
+{
+	u_char *tmp_buf;
+	size_t tmp_len;
+	loff_t start, end;
+	int ret, bytes_read;
+
+	if (IS_ALIGNED(from, 2) && IS_ALIGNED(len, 2))
+		return spi_nor_read_data(nor, from, len, buf);
+	else if (IS_ALIGNED(from, 2) && len > PAGE_SIZE)
+		return spi_nor_read_data(nor, from, round_down(len, PAGE_SIZE),
+					 buf);
+
+	tmp_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!tmp_buf)
+		return -ENOMEM;
+
+	start = round_down(from, 2);
+	end = round_up(from + len, 2);
+
+	/*
+	 * Avoid allocating too much memory. The requested read length might be
+	 * quite large. Allocating a buffer just as large (slightly bigger, in
+	 * fact) would put unnecessary memory pressure on the system.
+	 *
+	 * For example if the read is from 3 to 1M, then this will read from 2
+	 * to 4098. The reads from 4098 to 1M will then not need a temporary
+	 * buffer so they can proceed as normal.
+	 */
+	tmp_len = min_t(size_t, end - start, PAGE_SIZE);
+
+	ret = spi_nor_read_data(nor, start, tmp_len, tmp_buf);
+	if (ret == 0) {
+		ret = -EIO;
+		goto out;
+	}
+	if (ret < 0)
+		goto out;
+
+	/*
+	 * More bytes are read than actually requested, but that number can't be
+	 * reported to the calling function or it will confuse its calculations.
+	 * Calculate how many of the _requested_ bytes were read.
+	 */
+	bytes_read = ret;
+
+	if (from != start)
+		ret -= from - start;
+
+	/*
+	 * Only account for extra bytes at the end if they were actually read.
+	 * For example, if the total length was truncated because of temporary
+	 * buffer size limit then the adjustment for the extra bytes at the end
+	 * is not needed.
+	 */
+	if (start + bytes_read == end)
+		ret -= end - (from + len);
+
+	memcpy(buf, tmp_buf + (from - start), ret);
+out:
+	kfree(tmp_buf);
+	return ret;
+}
+
 static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
 			size_t *retlen, u_char *buf)
 {
@@ -2065,9 +2101,11 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
 	while (len) {
 		loff_t addr = from;
 
-		addr = spi_nor_convert_addr(nor, addr);
+		if (nor->read_proto == SNOR_PROTO_8_8_8_DTR)
+			ret = spi_nor_octal_dtr_read(nor, addr, len, buf);
+		else
+			ret = spi_nor_read_data(nor, addr, len, buf);
 
-		ret = spi_nor_read_data(nor, addr, len, buf);
 		if (ret == 0) {
 			/* We shouldn't see 0-length reads */
 			ret = -EIO;
@@ -2091,6 +2129,68 @@ read_err:
 }
 
 /*
+ * On Octal DTR capable flashes, writes cannot start or end at an odd address
+ * in Octal DTR mode. Extra 0xff bytes need to be appended or prepended to
+ * make sure the start address and end address are even. 0xff is used because
+ * on NOR flashes a program operation can only flip bits from 1 to 0, not the
+ * other way round. 0 to 1 flip needs to happen via erases.
+ */
+static int spi_nor_octal_dtr_write(struct spi_nor *nor, loff_t to, size_t len,
+				   const u8 *buf)
+{
+	u8 *tmp_buf;
+	size_t bytes_written;
+	loff_t start, end;
+	int ret;
+
+	if (IS_ALIGNED(to, 2) && IS_ALIGNED(len, 2))
+		return spi_nor_write_data(nor, to, len, buf);
+
+	tmp_buf = kmalloc(nor->params->page_size, GFP_KERNEL);
+	if (!tmp_buf)
+		return -ENOMEM;
+
+	memset(tmp_buf, 0xff, nor->params->page_size);
+
+	start = round_down(to, 2);
+	end = round_up(to + len, 2);
+
+	memcpy(tmp_buf + (to - start), buf, len);
+
+	ret = spi_nor_write_data(nor, start, end - start, tmp_buf);
+	if (ret == 0) {
+		ret = -EIO;
+		goto out;
+	}
+	if (ret < 0)
+		goto out;
+
+	/*
+	 * More bytes are written than actually requested, but that number can't
+	 * be reported to the calling function or it will confuse its
+	 * calculations. Calculate how many of the _requested_ bytes were
+	 * written.
+	 */
+	bytes_written = ret;
+
+	if (to != start)
+		ret -= to - start;
+
+	/*
+	 * Only account for extra bytes at the end if they were actually
+	 * written. For example, if for some reason the controller could only
+	 * complete a partial write then the adjustment for the extra bytes at
+	 * the end is not needed.
+	 */
+	if (start + bytes_written == end)
+		ret -= end - (to + len);
+
+out:
+	kfree(tmp_buf);
+	return ret;
+}
+
+/*
  * Write an address range to the nor chip.  Data must be written in
  * FLASH_PAGESIZE chunks.  The address range may be any size provided
  * it is within the physical boundaries.
@@ -2099,7 +2199,7 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
 	size_t *retlen, const u_char *buf)
 {
 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
-	size_t page_offset, page_remain, i;
+	size_t i;
 	ssize_t ret;
 	u32 page_size = nor->params->page_size;
 
@@ -2112,23 +2212,9 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
 	for (i = 0; i < len; ) {
 		ssize_t written;
 		loff_t addr = to + i;
-
-		/*
-		 * If page_size is a power of two, the offset can be quickly
-		 * calculated with an AND operation. On the other cases we
-		 * need to do a modulus operation (more expensive).
-		 */
-		if (is_power_of_2(page_size)) {
-			page_offset = addr & (page_size - 1);
-		} else {
-			u64 aux = addr;
-
-			page_offset = do_div(aux, page_size);
-		}
+		size_t page_offset = addr & (page_size - 1);
 		/* the size of data remaining on the first page */
-		page_remain = min_t(size_t, page_size - page_offset, len - i);
-
-		addr = spi_nor_convert_addr(nor, addr);
+		size_t page_remain = min_t(size_t, page_size - page_offset, len - i);
 
 		ret = spi_nor_lock_device(nor);
 		if (ret)
@@ -2140,7 +2226,12 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
 			goto write_err;
 		}
 
-		ret = spi_nor_write_data(nor, addr, page_remain, buf + i);
+		if (nor->write_proto == SNOR_PROTO_8_8_8_DTR)
+			ret = spi_nor_octal_dtr_write(nor, addr, page_remain,
+						      buf + i);
+		else
+			ret = spi_nor_write_data(nor, addr, page_remain,
+						 buf + i);
 		spi_nor_unlock_device(nor);
 		if (ret < 0)
 			goto write_err;
@@ -2368,6 +2459,16 @@ spi_nor_spimem_adjust_hwcaps(struct spi_nor *nor, u32 *hwcaps)
 					    &params->page_programs[ppidx]))
 			*hwcaps &= ~BIT(cap);
 	}
+
+	/* Some SPI controllers might not support CR read opcode. */
+	if (!(nor->flags & SNOR_F_NO_READ_CR)) {
+		struct spi_mem_op op = SPI_NOR_RDCR_OP(nor->bouncebuf);
+
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
+		if (spi_nor_spimem_check_op(nor, &op))
+			nor->flags |= SNOR_F_NO_READ_CR;
+	}
 }
 
 /**
@@ -2581,8 +2682,51 @@ static int spi_nor_select_erase(struct spi_nor *nor)
 	return 0;
 }
 
-static int spi_nor_default_setup(struct spi_nor *nor,
-				 const struct spi_nor_hwcaps *hwcaps)
+static int spi_nor_set_addr_nbytes(struct spi_nor *nor)
+{
+	if (nor->params->addr_nbytes) {
+		nor->addr_nbytes = nor->params->addr_nbytes;
+	} else if (nor->read_proto == SNOR_PROTO_8_8_8_DTR) {
+		/*
+		 * In 8D-8D-8D mode, one byte takes half a cycle to transfer. So
+		 * in this protocol an odd addr_nbytes cannot be used because
+		 * then the address phase would only span a cycle and a half.
+		 * Half a cycle would be left over. We would then have to start
+		 * the dummy phase in the middle of a cycle and so too the data
+		 * phase, and we will end the transaction with half a cycle left
+		 * over.
+		 *
+		 * Force all 8D-8D-8D flashes to use an addr_nbytes of 4 to
+		 * avoid this situation.
+		 */
+		nor->addr_nbytes = 4;
+	} else if (nor->info->addr_nbytes) {
+		nor->addr_nbytes = nor->info->addr_nbytes;
+	} else {
+		nor->addr_nbytes = 3;
+	}
+
+	if (nor->addr_nbytes == 3 && nor->params->size > 0x1000000) {
+		/* enable 4-byte addressing if the device exceeds 16MiB */
+		nor->addr_nbytes = 4;
+	}
+
+	if (nor->addr_nbytes > SPI_NOR_MAX_ADDR_NBYTES) {
+		dev_dbg(nor->dev, "The number of address bytes is too large: %u\n",
+			nor->addr_nbytes);
+		return -EINVAL;
+	}
+
+	/* Set 4byte opcodes when possible. */
+	if (nor->addr_nbytes == 4 && nor->flags & SNOR_F_4B_OPCODES &&
+	    !(nor->flags & SNOR_F_HAS_4BAIT))
+		spi_nor_set_4byte_opcodes(nor);
+
+	return 0;
+}
+
+static int spi_nor_setup(struct spi_nor *nor,
+			 const struct spi_nor_hwcaps *hwcaps)
 {
 	struct spi_nor_flash_parameter *params = nor->params;
 	u32 ignored_mask, shared_mask;
@@ -2639,64 +2783,6 @@ static int spi_nor_default_setup(struct spi_nor *nor,
 		return err;
 	}
 
-	return 0;
-}
-
-static int spi_nor_set_addr_nbytes(struct spi_nor *nor)
-{
-	if (nor->params->addr_nbytes) {
-		nor->addr_nbytes = nor->params->addr_nbytes;
-	} else if (nor->read_proto == SNOR_PROTO_8_8_8_DTR) {
-		/*
-		 * In 8D-8D-8D mode, one byte takes half a cycle to transfer. So
-		 * in this protocol an odd addr_nbytes cannot be used because
-		 * then the address phase would only span a cycle and a half.
-		 * Half a cycle would be left over. We would then have to start
-		 * the dummy phase in the middle of a cycle and so too the data
-		 * phase, and we will end the transaction with half a cycle left
-		 * over.
-		 *
-		 * Force all 8D-8D-8D flashes to use an addr_nbytes of 4 to
-		 * avoid this situation.
-		 */
-		nor->addr_nbytes = 4;
-	} else if (nor->info->addr_nbytes) {
-		nor->addr_nbytes = nor->info->addr_nbytes;
-	} else {
-		nor->addr_nbytes = 3;
-	}
-
-	if (nor->addr_nbytes == 3 && nor->params->size > 0x1000000) {
-		/* enable 4-byte addressing if the device exceeds 16MiB */
-		nor->addr_nbytes = 4;
-	}
-
-	if (nor->addr_nbytes > SPI_NOR_MAX_ADDR_NBYTES) {
-		dev_dbg(nor->dev, "The number of address bytes is too large: %u\n",
-			nor->addr_nbytes);
-		return -EINVAL;
-	}
-
-	/* Set 4byte opcodes when possible. */
-	if (nor->addr_nbytes == 4 && nor->flags & SNOR_F_4B_OPCODES &&
-	    !(nor->flags & SNOR_F_HAS_4BAIT))
-		spi_nor_set_4byte_opcodes(nor);
-
-	return 0;
-}
-
-static int spi_nor_setup(struct spi_nor *nor,
-			 const struct spi_nor_hwcaps *hwcaps)
-{
-	int ret;
-
-	if (nor->params->setup)
-		ret = nor->params->setup(nor, hwcaps);
-	else
-		ret = spi_nor_default_setup(nor, hwcaps);
-	if (ret)
-		return ret;
-
 	return spi_nor_set_addr_nbytes(nor);
 }
 
@@ -2965,15 +3051,10 @@ static void spi_nor_init_default_params(struct spi_nor *nor)
 	params->page_size = info->page_size ?: SPI_NOR_DEFAULT_PAGE_SIZE;
 	params->n_banks = info->n_banks ?: SPI_NOR_DEFAULT_N_BANKS;
 
-	if (!(info->flags & SPI_NOR_NO_FR)) {
-		/* Default to Fast Read for DT and non-DT platform devices. */
+	/* Default to Fast Read for non-DT and enable it if requested by DT. */
+	if (!np || of_property_read_bool(np, "m25p,fast-read"))
 		params->hwcaps.mask |= SNOR_HWCAPS_READ_FAST;
 
-		/* Mask out Fast Read if not requested at DT instantiation. */
-		if (np && !of_property_read_bool(np, "m25p,fast-read"))
-			params->hwcaps.mask &= ~SNOR_HWCAPS_READ_FAST;
-	}
-
 	/* (Fast) Read settings. */
 	params->hwcaps.mask |= SNOR_HWCAPS_READ;
 	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ],
@@ -3055,7 +3136,14 @@ static int spi_nor_init_params(struct spi_nor *nor)
 		spi_nor_init_params_deprecated(nor);
 	}
 
-	return spi_nor_late_init_params(nor);
+	ret = spi_nor_late_init_params(nor);
+	if (ret)
+		return ret;
+
+	if (WARN_ON(!is_power_of_2(nor->params->page_size)))
+		return -EINVAL;
+
+	return 0;
 }
 
 /** spi_nor_set_octal_dtr() - enable or disable Octal DTR I/O.
@@ -3321,7 +3409,8 @@ static const struct flash_info *spi_nor_match_name(struct spi_nor *nor,
 
 	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
 		for (j = 0; j < manufacturers[i]->nparts; j++) {
-			if (!strcmp(name, manufacturers[i]->parts[j].name)) {
+			if (manufacturers[i]->parts[j].name &&
+			    !strcmp(name, manufacturers[i]->parts[j].name)) {
 				nor->manufacturer = manufacturers[i];
 				return &manufacturers[i]->parts[j];
 			}
@@ -3338,32 +3427,28 @@ static const struct flash_info *spi_nor_get_flash_info(struct spi_nor *nor,
 
 	if (name)
 		info = spi_nor_match_name(nor, name);
-	/* Try to auto-detect if chip name wasn't specified or not found */
-	if (!info)
-		return spi_nor_detect(nor);
-
 	/*
-	 * If caller has specified name of flash model that can normally be
-	 * detected using JEDEC, let's verify it.
+	 * Auto-detect if chip name wasn't specified or not found, or the chip
+	 * has an ID. If the chip supposedly has an ID, we also do an
+	 * auto-detection to compare it later.
 	 */
-	if (name && info->id) {
+	if (!info || info->id) {
 		const struct flash_info *jinfo;
 
 		jinfo = spi_nor_detect(nor);
-		if (IS_ERR(jinfo)) {
+		if (IS_ERR(jinfo))
 			return jinfo;
-		} else if (jinfo != info) {
-			/*
-			 * JEDEC knows better, so overwrite platform ID. We
-			 * can't trust partitions any longer, but we'll let
-			 * mtd apply them anyway, since some partitions may be
-			 * marked read-only, and we don't want to loose that
-			 * information, even if it's not 100% accurate.
-			 */
+
+		/*
+		 * If caller has specified name of flash model that can normally
+		 * be detected using JEDEC, let's verify it.
+		 */
+		if (info && jinfo != info)
 			dev_warn(nor->dev, "found %s, expected %s\n",
 				 jinfo->name, info->name);
-			info = jinfo;
-		}
+
+		/* If info was set before, JEDEC knows better. */
+		info = jinfo;
 	}
 
 	return info;
@@ -3616,7 +3701,8 @@ static int spi_nor_create_write_dirmap(struct spi_nor *nor)
 static int spi_nor_probe(struct spi_mem *spimem)
 {
 	struct spi_device *spi = spimem->spi;
-	struct flash_platform_data *data = dev_get_platdata(&spi->dev);
+	struct device *dev = &spi->dev;
+	struct flash_platform_data *data = dev_get_platdata(dev);
 	struct spi_nor *nor;
 	/*
 	 * Enable all caps by default. The core will mask them after
@@ -3626,13 +3712,17 @@ static int spi_nor_probe(struct spi_mem *spimem)
 	char *flash_name;
 	int ret;
 
-	nor = devm_kzalloc(&spi->dev, sizeof(*nor), GFP_KERNEL);
+	ret = devm_regulator_get_enable(dev, "vcc");
+	if (ret)
+		return ret;
+
+	nor = devm_kzalloc(dev, sizeof(*nor), GFP_KERNEL);
 	if (!nor)
 		return -ENOMEM;
 
 	nor->spimem = spimem;
-	nor->dev = &spi->dev;
-	spi_nor_set_flash_node(nor, spi->dev.of_node);
+	nor->dev = dev;
+	spi_nor_set_flash_node(nor, dev->of_node);
 
 	spi_mem_set_drvdata(spimem, nor);
 
@@ -3668,9 +3758,8 @@ static int spi_nor_probe(struct spi_mem *spimem)
 	 */
 	if (nor->params->page_size > PAGE_SIZE) {
 		nor->bouncebuf_size = nor->params->page_size;
-		devm_kfree(nor->dev, nor->bouncebuf);
-		nor->bouncebuf = devm_kmalloc(nor->dev,
-					      nor->bouncebuf_size,
+		devm_kfree(dev, nor->bouncebuf);
+		nor->bouncebuf = devm_kmalloc(dev, nor->bouncebuf_size,
 					      GFP_KERNEL);
 		if (!nor->bouncebuf)
 			return -ENOMEM;