[PATCH v3 2/2] mtd: spi-nor: add driver for STM32 quad spi flash controller
From: Ludovic Barre
Date: Wed Apr 12 2017 - 13:08:09 EST
From: Ludovic Barre <ludovic.barre@xxxxxx>
The quadspi is a specialized communication interface targeting single,
dual or quad SPI Flash memories.
It can operate in any of the following modes:
-indirect mode: all the operations are performed using the quadspi
registers
-read memory-mapped mode: the external Flash memory is mapped to the
microcontroller address space and is seen by the system as if it was
an internal memory
Signed-off-by: Ludovic Barre <ludovic.barre@xxxxxx>
---
drivers/mtd/spi-nor/Kconfig | 7 +
drivers/mtd/spi-nor/Makefile | 1 +
drivers/mtd/spi-nor/stm32-quadspi.c | 693 ++++++++++++++++++++++++++++++++++++
3 files changed, 701 insertions(+)
create mode 100644 drivers/mtd/spi-nor/stm32-quadspi.c
diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
index 7252087..bfdfb1e 100644
--- a/drivers/mtd/spi-nor/Kconfig
+++ b/drivers/mtd/spi-nor/Kconfig
@@ -106,4 +106,11 @@ config SPI_INTEL_SPI_PLATFORM
To compile this driver as a module, choose M here: the module
will be called intel-spi-platform.
+config SPI_STM32_QUADSPI
+ tristate "STM32 Quad SPI controller"
+ depends on ARCH_STM32
+ help
+ This enables support for the STM32 Quad SPI controller.
+ We only connect the NOR to this controller.
+
endif # MTD_SPI_NOR
diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
index 72238a7..285aab8 100644
--- a/drivers/mtd/spi-nor/Makefile
+++ b/drivers/mtd/spi-nor/Makefile
@@ -8,3 +8,4 @@ obj-$(CONFIG_MTD_MT81xx_NOR) += mtk-quadspi.o
obj-$(CONFIG_SPI_NXP_SPIFI) += nxp-spifi.o
obj-$(CONFIG_SPI_INTEL_SPI) += intel-spi.o
obj-$(CONFIG_SPI_INTEL_SPI_PLATFORM) += intel-spi-platform.o
+obj-$(CONFIG_SPI_STM32_QUADSPI) += stm32-quadspi.o
\ No newline at end of file
diff --git a/drivers/mtd/spi-nor/stm32-quadspi.c b/drivers/mtd/spi-nor/stm32-quadspi.c
new file mode 100644
index 0000000..9e90dee
--- /dev/null
+++ b/drivers/mtd/spi-nor/stm32-quadspi.c
@@ -0,0 +1,693 @@
+/*
+ * stm32_quadspi.c
+ *
+ * Copyright (C) 2017, Ludovic Barre
+ *
+ * License terms: GNU General Public License (GPL), version 2
+ */
+#include <linux/clk.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/spi-nor.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+#define QUADSPI_CR 0x00
+#define CR_EN BIT(0)
+#define CR_ABORT BIT(1)
+#define CR_DMAEN BIT(2)
+#define CR_TCEN BIT(3)
+#define CR_SSHIFT BIT(4)
+#define CR_DFM BIT(6)
+#define CR_FSEL BIT(7)
+#define CR_FTHRES_SHIFT 8
+#define CR_FTHRES_MASK GENMASK(12, 8)
+#define CR_FTHRES(n) (((n) << CR_FTHRES_SHIFT) & CR_FTHRES_MASK)
+#define CR_TEIE BIT(16)
+#define CR_TCIE BIT(17)
+#define CR_FTIE BIT(18)
+#define CR_SMIE BIT(19)
+#define CR_TOIE BIT(20)
+#define CR_PRESC_SHIFT 24
+#define CR_PRESC_MASK GENMASK(31, 24)
+#define CR_PRESC(n) (((n) << CR_PRESC_SHIFT) & CR_PRESC_MASK)
+
+#define QUADSPI_DCR 0x04
+#define DCR_CSHT_SHIFT 8
+#define DCR_CSHT_MASK GENMASK(10, 8)
+#define DCR_CSHT(n) (((n) << DCR_CSHT_SHIFT) & DCR_CSHT_MASK)
+#define DCR_FSIZE_SHIFT 16
+#define DCR_FSIZE_MASK GENMASK(20, 16)
+#define DCR_FSIZE(n) (((n) << DCR_FSIZE_SHIFT) & DCR_FSIZE_MASK)
+
+#define QUADSPI_SR 0x08
+#define SR_TEF BIT(0)
+#define SR_TCF BIT(1)
+#define SR_FTF BIT(2)
+#define SR_SMF BIT(3)
+#define SR_TOF BIT(4)
+#define SR_BUSY BIT(5)
+#define SR_FLEVEL_SHIFT 8
+#define SR_FLEVEL_MASK GENMASK(13, 8)
+
+#define QUADSPI_FCR 0x0c
+#define FCR_CTCF BIT(1)
+
+#define QUADSPI_DLR 0x10
+
+#define QUADSPI_CCR 0x14
+#define CCR_INST_SHIFT 0
+#define CCR_INST_MASK GENMASK(7, 0)
+#define CCR_INST(n) (((n) << CCR_INST_SHIFT) & CCR_INST_MASK)
+#define CCR_IMODE_NONE (0 << 8)
+#define CCR_IMODE_1 (1 << 8)
+#define CCR_IMODE_2 (2 << 8)
+#define CCR_IMODE_4 (3 << 8)
+#define CCR_ADMODE_NONE (0 << 10)
+#define CCR_ADMODE_1 (1 << 10)
+#define CCR_ADMODE_2 (2 << 10)
+#define CCR_ADMODE_4 (3 << 10)
+#define CCR_ADSIZE_SHIFT 12
+#define CCR_ADSIZE_MASK GENMASK(13, 12)
+#define CCR_ADSIZE(n) (((n) << CCR_ADSIZE_SHIFT) & CCR_ADSIZE_MASK)
+#define CCR_ABMODE_NONE (0 << 14)
+#define CCR_ABMODE_1 (1 << 14)
+#define CCR_ABMODE_2 (2 << 14)
+#define CCR_ABMODE_4 (3 << 14)
+#define CCR_ABSIZE_8 (0 << 16)
+#define CCR_ABSIZE_16 (1 << 16)
+#define CCR_ABSIZE_24 (2 << 16)
+#define CCR_ABSIZE_32 (3 << 16)
+#define CCR_DCYC_SHIFT 18
+#define CCR_DCYC_MASK GENMASK(22, 18)
+#define CCR_DCYC(n) (((n) << CCR_DCYC_SHIFT) & CCR_DCYC_MASK)
+#define CCR_DMODE_NONE (0 << 24)
+#define CCR_DMODE_1 (1 << 24)
+#define CCR_DMODE_2 (2 << 24)
+#define CCR_DMODE_4 (3 << 24)
+#define CCR_FMODE_INDW (0 << 26)
+#define CCR_FMODE_INDR (1 << 26)
+#define CCR_FMODE_APM (2 << 26)
+#define CCR_FMODE_MM (3 << 26)
+
+#define QUADSPI_AR 0x18
+#define QUADSPI_ABR 0x1c
+#define QUADSPI_DR 0x20
+#define QUADSPI_PSMKR 0x24
+#define QUADSPI_PSMAR 0x28
+#define QUADSPI_PIR 0x2c
+#define QUADSPI_LPTR 0x30
+#define LPTR_DFT_TIMEOUT 0x10
+
+#define FSIZE_VAL(size) (__fls(size) - 1)
+
+#define STM32_MAX_MMAP_SZ SZ_256M
+#define STM32_MAX_NORCHIP 2
+
+#define STM32_QSPI_FIFO_TIMEOUT_US 30000
+#define STM32_QSPI_BUSY_TIMEOUT_US 100000
+
+struct stm32_qspi_flash {
+ struct spi_nor nor;
+ u32 cs;
+ u32 fsize;
+ u32 presc;
+ u32 read_mode;
+ struct stm32_qspi *qspi;
+};
+
+struct stm32_qspi {
+ struct device *dev;
+ void __iomem *io_base;
+ void __iomem *mm_base;
+ resource_size_t mm_size;
+ u32 nor_num;
+ struct clk *clk;
+ u32 clk_rate;
+ struct stm32_qspi_flash flash[STM32_MAX_NORCHIP];
+ struct completion cmd_completion;
+
+ /*
+ * to protect device configuration, could be different between
+ * 2 flash access (bk1, bk2)
+ */
+ struct mutex lock;
+};
+
+struct stm32_qspi_cmd {
+ u8 addr_width;
+ u8 dummy;
+ bool tx_data;
+ u8 opcode;
+ u32 framemode;
+ u32 qspimode;
+ u32 addr;
+ size_t len;
+ void *buf;
+};
+
+static int stm32_qspi_wait_cmd(struct stm32_qspi *qspi)
+{
+ u32 cr;
+ int err = 0;
+
+ if (readl_relaxed(qspi->io_base + QUADSPI_SR) & SR_TCF)
+ return 0;
+
+ reinit_completion(&qspi->cmd_completion);
+ cr = readl_relaxed(qspi->io_base + QUADSPI_CR);
+ writel_relaxed(cr | CR_TCIE, qspi->io_base + QUADSPI_CR);
+
+ if (!wait_for_completion_interruptible_timeout(&qspi->cmd_completion,
+ msecs_to_jiffies(1000)))
+ err = -ETIMEDOUT;
+
+ writel_relaxed(cr, qspi->io_base + QUADSPI_CR);
+ return err;
+}
+
+static int stm32_qspi_wait_nobusy(struct stm32_qspi *qspi)
+{
+ u32 sr;
+
+ return readl_relaxed_poll_timeout(qspi->io_base + QUADSPI_SR, sr,
+ !(sr & SR_BUSY), 10,
+ STM32_QSPI_BUSY_TIMEOUT_US);
+}
+
+static void stm32_qspi_set_framemode(struct spi_nor *nor,
+ struct stm32_qspi_cmd *cmd, bool read)
+{
+ u32 dmode = CCR_DMODE_1;
+
+ cmd->framemode = CCR_IMODE_1;
+
+ if (read) {
+ switch (nor->flash_read) {
+ case SPI_NOR_NORMAL:
+ case SPI_NOR_FAST:
+ dmode = CCR_DMODE_1;
+ break;
+ case SPI_NOR_DUAL:
+ dmode = CCR_DMODE_2;
+ break;
+ case SPI_NOR_QUAD:
+ dmode = CCR_DMODE_4;
+ break;
+ }
+ }
+
+ cmd->framemode |= cmd->tx_data ? dmode : 0;
+ cmd->framemode |= cmd->addr_width ? CCR_ADMODE_1 : 0;
+}
+
+static void stm32_qspi_read_fifo(u8 *val, void __iomem *addr)
+{
+ *val = readb_relaxed(addr);
+}
+
+static void stm32_qspi_write_fifo(u8 *val, void __iomem *addr)
+{
+ writeb_relaxed(*val, addr);
+}
+
+static int stm32_qspi_tx_poll(struct stm32_qspi *qspi,
+ const struct stm32_qspi_cmd *cmd)
+{
+ void (*tx_fifo)(u8 *, void __iomem *);
+ u32 len = cmd->len, sr;
+ u8 *buf = cmd->buf;
+ int ret;
+
+ if (cmd->qspimode == CCR_FMODE_INDW)
+ tx_fifo = stm32_qspi_write_fifo;
+ else
+ tx_fifo = stm32_qspi_read_fifo;
+
+ while (len--) {
+ ret = readl_relaxed_poll_timeout(qspi->io_base + QUADSPI_SR,
+ sr, (sr & SR_FTF), 10,
+ STM32_QSPI_FIFO_TIMEOUT_US);
+ if (ret) {
+ dev_err(qspi->dev, "fifo timeout (stat:%#x)\n", sr);
+ break;
+ }
+ tx_fifo(buf++, qspi->io_base + QUADSPI_DR);
+ }
+
+ return ret;
+}
+
+static int stm32_qspi_tx_mm(struct stm32_qspi *qspi,
+ const struct stm32_qspi_cmd *cmd)
+{
+ memcpy_fromio(cmd->buf, qspi->mm_base + cmd->addr, cmd->len);
+ return 0;
+}
+
+static int stm32_qspi_tx(struct stm32_qspi *qspi,
+ const struct stm32_qspi_cmd *cmd)
+{
+ if (!cmd->tx_data)
+ return 0;
+
+ if (cmd->qspimode == CCR_FMODE_MM)
+ return stm32_qspi_tx_mm(qspi, cmd);
+
+ return stm32_qspi_tx_poll(qspi, cmd);
+}
+
+static int stm32_qspi_send(struct stm32_qspi_flash *flash,
+ const struct stm32_qspi_cmd *cmd)
+{
+ struct stm32_qspi *qspi = flash->qspi;
+ u32 ccr, dcr, cr;
+ int err;
+
+ err = stm32_qspi_wait_nobusy(qspi);
+ if (err)
+ goto abort;
+
+ dcr = readl_relaxed(qspi->io_base + QUADSPI_DCR) & ~DCR_FSIZE_MASK;
+ dcr |= DCR_FSIZE(flash->fsize);
+ writel_relaxed(dcr, qspi->io_base + QUADSPI_DCR);
+
+ cr = readl_relaxed(qspi->io_base + QUADSPI_CR);
+ cr &= ~CR_PRESC_MASK & ~CR_FSEL;
+ cr |= CR_PRESC(flash->presc);
+ cr |= flash->cs ? CR_FSEL : 0;
+ writel_relaxed(cr, qspi->io_base + QUADSPI_CR);
+
+ if (cmd->tx_data)
+ writel_relaxed(cmd->len - 1, qspi->io_base + QUADSPI_DLR);
+
+ ccr = cmd->framemode | cmd->qspimode;
+
+ if (cmd->dummy)
+ ccr |= CCR_DCYC(cmd->dummy);
+
+ if (cmd->addr_width)
+ ccr |= CCR_ADSIZE(cmd->addr_width - 1);
+
+ ccr |= CCR_INST(cmd->opcode);
+ writel_relaxed(ccr, qspi->io_base + QUADSPI_CCR);
+
+ if (cmd->addr_width && cmd->qspimode != CCR_FMODE_MM)
+ writel_relaxed(cmd->addr, qspi->io_base + QUADSPI_AR);
+
+ err = stm32_qspi_tx(qspi, cmd);
+ if (err)
+ goto abort;
+
+ if (cmd->qspimode != CCR_FMODE_MM) {
+ err = stm32_qspi_wait_cmd(qspi);
+ if (err)
+ goto abort;
+ writel_relaxed(FCR_CTCF, qspi->io_base + QUADSPI_FCR);
+ }
+
+ return err;
+
+abort:
+ cr = readl_relaxed(qspi->io_base + QUADSPI_CR) | CR_ABORT;
+ writel_relaxed(cr, qspi->io_base + QUADSPI_CR);
+
+ dev_err(qspi->dev, "%s abort err:%d\n", __func__, err);
+ return err;
+}
+
+static int stm32_qspi_read_reg(struct spi_nor *nor,
+ u8 opcode, u8 *buf, int len)
+{
+ struct stm32_qspi_flash *flash = nor->priv;
+ struct device *dev = flash->qspi->dev;
+ struct stm32_qspi_cmd cmd;
+
+ dev_dbg(dev, "read_reg: cmd:%#.2x buf:%p len:%#x\n", opcode, buf, len);
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.opcode = opcode;
+ cmd.tx_data = true;
+ cmd.len = len;
+ cmd.buf = buf;
+ cmd.qspimode = CCR_FMODE_INDR;
+
+ stm32_qspi_set_framemode(nor, &cmd, false);
+
+ return stm32_qspi_send(flash, &cmd);
+}
+
+static int stm32_qspi_write_reg(struct spi_nor *nor, u8 opcode,
+ u8 *buf, int len)
+{
+ struct stm32_qspi_flash *flash = nor->priv;
+ struct device *dev = flash->qspi->dev;
+ struct stm32_qspi_cmd cmd;
+
+ dev_dbg(dev, "write_reg: cmd:%#.2x buf:%p len:%#x\n", opcode, buf, len);
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.opcode = opcode;
+ cmd.tx_data = !!(buf && len > 0);
+ cmd.len = len;
+ cmd.buf = buf;
+ cmd.qspimode = CCR_FMODE_INDW;
+
+ stm32_qspi_set_framemode(nor, &cmd, false);
+
+ return stm32_qspi_send(flash, &cmd);
+}
+
+static ssize_t stm32_qspi_read(struct spi_nor *nor, loff_t from, size_t len,
+ u_char *buf)
+{
+ struct stm32_qspi_flash *flash = nor->priv;
+ struct stm32_qspi *qspi = flash->qspi;
+ struct stm32_qspi_cmd cmd;
+ int err;
+
+ dev_dbg(qspi->dev, "read(%#.2x): buf:%p from:%#.8x len:%#x\n",
+ nor->read_opcode, buf, (u32)from, len);
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.opcode = nor->read_opcode;
+ cmd.addr_width = nor->addr_width;
+ cmd.addr = (u32)from;
+ cmd.tx_data = true;
+ cmd.dummy = nor->read_dummy;
+ cmd.len = len;
+ cmd.buf = buf;
+ cmd.qspimode = flash->read_mode;
+
+ stm32_qspi_set_framemode(nor, &cmd, true);
+ err = stm32_qspi_send(flash, &cmd);
+
+ return err ? err : len;
+}
+
+static ssize_t stm32_qspi_write(struct spi_nor *nor, loff_t to, size_t len,
+ const u_char *buf)
+{
+ struct stm32_qspi_flash *flash = nor->priv;
+ struct device *dev = flash->qspi->dev;
+ struct stm32_qspi_cmd cmd;
+ int err;
+
+ dev_dbg(dev, "write(%#.2x): buf:%p to:%#.8x len:%#x\n",
+ nor->program_opcode, buf, (u32)to, len);
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.opcode = nor->program_opcode;
+ cmd.addr_width = nor->addr_width;
+ cmd.addr = (u32)to;
+ cmd.tx_data = true;
+ cmd.len = len;
+ cmd.buf = (void *)buf;
+ cmd.qspimode = CCR_FMODE_INDW;
+
+ stm32_qspi_set_framemode(nor, &cmd, false);
+ err = stm32_qspi_send(flash, &cmd);
+
+ return err ? err : len;
+}
+
+static int stm32_qspi_erase(struct spi_nor *nor, loff_t offs)
+{
+ struct stm32_qspi_flash *flash = nor->priv;
+ struct device *dev = flash->qspi->dev;
+ struct stm32_qspi_cmd cmd;
+
+ dev_dbg(dev, "erase(%#.2x):offs:%#x\n", nor->erase_opcode, (u32)offs);
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.opcode = nor->erase_opcode;
+ cmd.addr_width = nor->addr_width;
+ cmd.addr = (u32)offs;
+ cmd.qspimode = CCR_FMODE_INDW;
+
+ stm32_qspi_set_framemode(nor, &cmd, false);
+
+ return stm32_qspi_send(flash, &cmd);
+}
+
+static irqreturn_t stm32_qspi_irq(int irq, void *dev_id)
+{
+ struct stm32_qspi *qspi = (struct stm32_qspi *)dev_id;
+ u32 cr, sr, fcr = 0;
+
+ cr = readl_relaxed(qspi->io_base + QUADSPI_CR);
+ sr = readl_relaxed(qspi->io_base + QUADSPI_SR);
+
+ if ((cr & CR_TCIE) && (sr & SR_TCF)) {
+ /* tx complete */
+ fcr |= FCR_CTCF;
+ complete(&qspi->cmd_completion);
+ } else {
+ dev_info_ratelimited(qspi->dev, "spurious interrupt\n");
+ }
+
+ writel_relaxed(fcr, qspi->io_base + QUADSPI_FCR);
+
+ return IRQ_HANDLED;
+}
+
+static int stm32_qspi_prep(struct spi_nor *nor, enum spi_nor_ops ops)
+{
+ struct stm32_qspi_flash *flash = nor->priv;
+ struct stm32_qspi *qspi = flash->qspi;
+
+ mutex_lock(&qspi->lock);
+ return 0;
+}
+
+static void stm32_qspi_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
+{
+ struct stm32_qspi_flash *flash = nor->priv;
+ struct stm32_qspi *qspi = flash->qspi;
+
+ mutex_unlock(&qspi->lock);
+}
+
+static int stm32_qspi_flash_setup(struct stm32_qspi *qspi,
+ struct device_node *np)
+{
+ u32 width, flash_read, presc, cs_num, max_rate = 0;
+ struct stm32_qspi_flash *flash;
+ struct mtd_info *mtd;
+ int ret;
+
+ of_property_read_u32(np, "reg", &cs_num);
+ if (cs_num >= STM32_MAX_NORCHIP)
+ return -EINVAL;
+
+ of_property_read_u32(np, "spi-max-frequency", &max_rate);
+ if (!max_rate)
+ return -EINVAL;
+
+ presc = DIV_ROUND_UP(qspi->clk_rate, max_rate) - 1;
+
+ if (of_property_read_u32(np, "spi-rx-bus-width", &width))
+ width = 1;
+
+ if (width == 4)
+ flash_read = SPI_NOR_QUAD;
+ else if (width == 2)
+ flash_read = SPI_NOR_DUAL;
+ else if (width == 1)
+ flash_read = SPI_NOR_NORMAL;
+ else
+ return -EINVAL;
+
+ flash = &qspi->flash[cs_num];
+ flash->qspi = qspi;
+ flash->cs = cs_num;
+ flash->presc = presc;
+
+ flash->nor.dev = qspi->dev;
+ spi_nor_set_flash_node(&flash->nor, np);
+ flash->nor.priv = flash;
+ mtd = &flash->nor.mtd;
+ mtd->priv = &flash->nor;
+
+ flash->nor.read = stm32_qspi_read;
+ flash->nor.write = stm32_qspi_write;
+ flash->nor.erase = stm32_qspi_erase;
+ flash->nor.read_reg = stm32_qspi_read_reg;
+ flash->nor.write_reg = stm32_qspi_write_reg;
+ flash->nor.prepare = stm32_qspi_prep;
+ flash->nor.unprepare = stm32_qspi_unprep;
+
+ writel_relaxed(LPTR_DFT_TIMEOUT, qspi->io_base + QUADSPI_LPTR);
+
+ writel_relaxed(CR_PRESC(presc) | CR_FTHRES(3) | CR_TCEN | CR_SSHIFT
+ | CR_EN, qspi->io_base + QUADSPI_CR);
+
+ /*
+ * in stm32 qspi controller, QUADSPI_DCR register has a fsize field
+ * which define the size of nor flash.
+ * if fsize is NULL, the controller can't sent spi-nor command.
+ * set a temporary value just to discover the nor flash with
+ * "spi_nor_scan". After, the right value (mtd->size) can be set.
+ */
+ flash->fsize = FSIZE_VAL(SZ_1K);
+
+ ret = spi_nor_scan(&flash->nor, NULL, flash_read);
+ if (ret) {
+ dev_err(qspi->dev, "device scan failed\n");
+ return ret;
+ }
+
+ flash->fsize = FSIZE_VAL(mtd->size);
+
+ flash->read_mode = CCR_FMODE_MM;
+ if (mtd->size > qspi->mm_size)
+ flash->read_mode = CCR_FMODE_INDR;
+
+ writel_relaxed(DCR_CSHT(1), qspi->io_base + QUADSPI_DCR);
+
+ ret = mtd_device_register(mtd, NULL, 0);
+ if (ret) {
+ dev_err(qspi->dev, "mtd device parse failed\n");
+ return ret;
+ }
+
+ dev_dbg(qspi->dev, "read mm:%s cs:%d bus:%d\n",
+ flash->read_mode == CCR_FMODE_MM ? "yes" : "no", cs_num, width);
+
+ return 0;
+}
+
+static void stm32_qspi_mtd_free(struct stm32_qspi *qspi)
+{
+ int i;
+
+ for (i = 0; i < STM32_MAX_NORCHIP; i++) {
+ if (qspi->flash[i].qspi)
+ mtd_device_unregister(&qspi->flash[i].nor.mtd);
+ }
+}
+
+static int stm32_qspi_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *flash_np;
+ struct reset_control *rstc;
+ struct stm32_qspi *qspi;
+ struct resource *res;
+ int ret, irq;
+
+ qspi = devm_kzalloc(dev, sizeof(*qspi), GFP_KERNEL);
+ if (!qspi)
+ return -ENOMEM;
+
+ qspi->nor_num = of_get_child_count(dev->of_node);
+ if (!qspi->nor_num || qspi->nor_num > STM32_MAX_NORCHIP)
+ return -ENODEV;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi");
+ qspi->io_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(qspi->io_base))
+ return PTR_ERR(qspi->io_base);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mm");
+ qspi->mm_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(qspi->mm_base))
+ return PTR_ERR(qspi->mm_base);
+
+ qspi->mm_size = resource_size(res);
+
+ irq = platform_get_irq(pdev, 0);
+ ret = devm_request_irq(dev, irq, stm32_qspi_irq, 0,
+ dev_name(dev), qspi);
+ if (ret) {
+ dev_err(dev, "failed to request irq\n");
+ return ret;
+ }
+
+ init_completion(&qspi->cmd_completion);
+
+ qspi->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(qspi->clk))
+ return PTR_ERR(qspi->clk);
+
+ qspi->clk_rate = clk_get_rate(qspi->clk);
+ if (!qspi->clk_rate)
+ return -EINVAL;
+
+ ret = clk_prepare_enable(qspi->clk);
+ if (ret) {
+ dev_err(dev, "can not enable the clock\n");
+ return ret;
+ }
+
+ rstc = devm_reset_control_get(dev, NULL);
+ if (!IS_ERR(rstc)) {
+ reset_control_assert(rstc);
+ udelay(2);
+ reset_control_deassert(rstc);
+ }
+
+ qspi->dev = dev;
+ platform_set_drvdata(pdev, qspi);
+ mutex_init(&qspi->lock);
+
+ for_each_available_child_of_node(dev->of_node, flash_np) {
+ ret = stm32_qspi_flash_setup(qspi, flash_np);
+ if (ret) {
+ dev_err(dev, "unable to setup flash chip\n");
+ goto err_flash;
+ }
+ }
+
+ return 0;
+
+err_flash:
+ mutex_destroy(&qspi->lock);
+ stm32_qspi_mtd_free(qspi);
+
+ clk_disable_unprepare(qspi->clk);
+ return ret;
+}
+
+static int stm32_qspi_remove(struct platform_device *pdev)
+{
+ struct stm32_qspi *qspi = platform_get_drvdata(pdev);
+
+ /* disable qspi */
+ writel_relaxed(0, qspi->io_base + QUADSPI_CR);
+
+ stm32_qspi_mtd_free(qspi);
+ mutex_destroy(&qspi->lock);
+
+ clk_disable_unprepare(qspi->clk);
+ return 0;
+}
+
+static const struct of_device_id stm32_qspi_match[] = {
+ {.compatible = "st,stm32f469-qspi"},
+ {}
+};
+MODULE_DEVICE_TABLE(of, stm32_qspi_match);
+
+static struct platform_driver stm32_qspi_driver = {
+ .probe = stm32_qspi_probe,
+ .remove = stm32_qspi_remove,
+ .driver = {
+ .name = "stm32-quadspi",
+ .of_match_table = stm32_qspi_match,
+ },
+};
+module_platform_driver(stm32_qspi_driver);
+
+MODULE_ALIAS("platform:" DRIVER_NAME);
+MODULE_AUTHOR("Ludovic Barre <ludovic.barre@xxxxxx>");
+MODULE_DESCRIPTION("STMicroelectronics STM32 quad spi driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4