[PATCH] [PATCH v3] mtd:spi-nor: Add Altera Quad SPI Driver
Nga Chi
ngachi86 at gmail.com
Wed May 27 18:44:28 PDT 2015
On Thu, May 28, 2015 at 9:32 AM, Brian Norris
<computersforpeace at gmail.com> wrote:
> Hi Nga,
>
> Sorry for some delay here. This driver is mostly pretty good, and I
> think only a few very small tweaks are needed.
>
> (BTW, Rafal already made a few tiny comments, and I didn't see a follow
> up that fixes any of them.)
Thanks Brian for your reply. I will make the modification needed.
Because Rafal commented on this v3 and i want to wait for your
comments too, so that will be applied in coming v4.
>
> On Mon, Mar 16, 2015 at 01:16:22AM -0700, vndao at altera.com wrote:
>> From: VIET NGA DAO <vndao at altera.com>
>>
>> Altera Quad SPI Controller is a soft IP which enables access to Altera EPCQ and
>> EPCS flash chips. This patch adds driver for these devices.
>>
>> Signed-off-by: VIET NGA DAO <vndao at altera.com>
>>
>> ---
>> v3:
>> - Change altera_epcq driver name to altera_quadspi for more generic name
>> - Implement flash name searching in altera_quadspi.c instead of spi-nor
>> - Edit the altra quadspi info table in spi-nor
>> - Remove wait_til_ready in all read,write, erase, lock, unlock functions
>> - Merge .h and .c into 1 file
>>
>> v2:
>> - Change to spi_nor structure
>> - Add lock and unlock functions for spi_nor
>> - Simplify the altera_epcq_lock function
>> - Replace reg by compatible in device tree
>> ---
>> .../devicetree/bindings/mtd/altera_quadspi.txt | 45 ++
>> drivers/mtd/spi-nor/Kconfig | 8 +
>> drivers/mtd/spi-nor/Makefile | 1 +
>> drivers/mtd/spi-nor/altera_quadspi.c | 608 +++++++++++++++++++++
>> drivers/mtd/spi-nor/spi-nor.c | 11 +
>> 5 files changed, 673 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/mtd/altera_quadspi.txt
>> create mode 100644 drivers/mtd/spi-nor/altera_quadspi.c
>>
>> diff --git a/Documentation/devicetree/bindings/mtd/altera_quadspi.txt b/Documentation/devicetree/bindings/mtd/altera_quadspi.txt
>> new file mode 100644
>> index 0000000..f5bdd35
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/mtd/altera_quadspi.txt
>> @@ -0,0 +1,45 @@
>> +* MTD Altera QUADSPI driver
>> +
>> +Required properties:
>> +- compatible: Should be "altr,quadspi-1.0"
>> +- reg: Address and length of the register set for the device. It contains
>> + the information of registers in the same order as described by reg-names
>> +- reg-names: Should contain the reg names
>> + "csr_base": Should contain the register configuration base address
>> + "data_base": Should contain the data base address
>> +- is-epcs: boolean type.
>> + If present, the device contains EPCS flashes.
>> + Otherwise, it contains EPCQ flashes.
>
> Is this a property of the controller, or the flash? Seems like it should
> be in the subnode(s).
>
>> +- #address-cells: Must be <1>.
>> +- #size-cells: Must be <0>.
>> +- flash device tree subnode, there must be a node with the following fields:
>> + - compatible: Should contain the flash name
>
> You should list the names here.
>
>> + - #address-cells: please refer to /mtd/partition.txt
>> + - #size-cells: please refer to /mtd/partition.txt
>> + For partitions inside each flash, please refer to /mtd/partition.txt
>> +
>> +Example:
>> +
>> + quadspi_controller_0: quadspi at 0x000000000 {
>> + compatible = "altr,quadspi-1.0";
>> + reg = <0x00000001 0x00000000 0x00000020>,
>> + <0x00000000 0x00000000 0x02000000>;
>> + reg-names = "csr_base", "data_base";
>> + #address-cells = <1>;
>> + #size-cells = <0>;
>> + flash0: epcq256 at 0 {
>> + compatible = "epcq256-nonjedec";
>
> I don't think the "-nonjedec" part is necessary; it's not really
> relevant to the binding, and it probably isn't even necessary for the ID
> table in spi-nor.c. Just stick with names like "altr,epcq256". But you
> probably should include the "altr," prefix. That will still work fine
> with the modalias stuff.
>
>> + #address-cells = <1>;
>> + #size-cells = <1>;
>> + partition at 0 {
>> + /* 16 MB for raw data. */
>> + label = "EPCQ Flash 0 raw data";
>> + reg = <0x0 0x1000000>;
>> + };
>> + partition at 1000000 {
>> + /* 16 MB for jffs2 data. */
>> + label = "EPCQ Flash 0 JFFS 2";
>> + reg = <0x1000000 0x1000000>;
>> + };
>> + };
>> + }; //end quadspi at 0x000000000 (quadspi_controller_0)
>> diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
>> index 64a4f0e..b9eed6d 100644
>> --- a/drivers/mtd/spi-nor/Kconfig
>> +++ b/drivers/mtd/spi-nor/Kconfig
>> @@ -28,4 +28,12 @@ config SPI_FSL_QUADSPI
>> This enables support for the Quad SPI controller in master mode.
>> We only connect the NOR to this controller now.
>>
>> +config SPI_ALTERA_QUADSPI
>> + tristate "Support Altera EPCQ/EPCS Flash chips"
>> + depends on OF
>> + help
>> + This enables access to Altera EPCQ/EPCS flash chips, used for data
>> + storage. See the driver source for the current list,
>> + or to add other chips.
>> +
>> endif # MTD_SPI_NOR
>> diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
>> index 6a7ce14..1a36a72 100644
>> --- a/drivers/mtd/spi-nor/Makefile
>> +++ b/drivers/mtd/spi-nor/Makefile
>> @@ -1,2 +1,3 @@
>> obj-$(CONFIG_MTD_SPI_NOR) += spi-nor.o
>> obj-$(CONFIG_SPI_FSL_QUADSPI) += fsl-quadspi.o
>> +obj-$(CONFIG_SPI_ALTERA_QUADSPI) += altera_quadspi.o
>> diff --git a/drivers/mtd/spi-nor/altera_quadspi.c b/drivers/mtd/spi-nor/altera_quadspi.c
>
> Probably just use hyphens ("-") in the file name, not underscores ("_")
> to match the other files in that dir.
>
>> new file mode 100644
>> index 0000000..1d178d9
>> --- /dev/null
>> +++ b/drivers/mtd/spi-nor/altera_quadspi.c
>> @@ -0,0 +1,608 @@
>> +/*
>> + * Copyright (C) 2014 Altera Corporation. All rights reserved
>> + *
>> + * This program is free software; you can redistribute it and/or modify it
>> + * under the terms and conditions of the GNU General Public License,
>> + * version 2, as published by the Free Software Foundation.
>> + *
>> + * This program is distributed in the hope it will be useful, but WITHOUT
>> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
>> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
>> + * more details.
>> + *
>> + * You should have received a copy of the GNU General Public License along with
>> + * this program. If not, see <http://www.gnu.org/licenses/>.
>> + */
>> +
>> +#include <linux/clk.h>
>> +#include <linux/delay.h>
>> +#include <linux/device.h>
>> +#include <linux/err.h>
>> +#include <linux/errno.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/io.h>
>> +#include <linux/ioport.h>
>> +#include <linux/jiffies.h>
>> +#include <linux/kernel.h>
>> +#include <linux/log2.h>
>> +#include <linux/module.h>
>> +#include <linux/mod_devicetable.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_address.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/sched.h>
>> +
>> +#define ALTERA_QUADSPI_RESOURCE_NAME "altera_quadspi"
>> +
>> +/* max possible slots for serial flash chip in the QUADSPI controller */
>> +#define MAX_NUM_FLASH_CHIP 3
>> +#define EPCS_OPCODE_ID 1
>> +#define EPCQ_OPCODE_ID 2
>> +#define WRITE_CHECK 1
>> +#define ERASE_CHECK 0
>> +
>> +/* Define max times to check status register before we give up. */
>> +#define QUADSPI_MAX_TIME_OUT (40 * HZ)
>> +
>> +/* defines for status register */
>> +#define QUADSPI_SR_REG 0x0
>> +#define QUADSPI_SR_WIP_MASK 0x00000001
>> +#define QUADSPI_SR_WIP 0x1
>> +#define QUADSPI_SR_WEL 0x2
>> +#define QUADSPI_SR_BP0 0x4
>> +#define QUADSPI_SR_BP1 0x8
>> +#define QUADSPI_SR_BP2 0x10
>> +#define QUADSPI_SR_BP3 0x40
>> +#define QUADSPI_SR_TB 0x20
>> +#define QUADSPI_SR_MASK 0x0000000F
>> +
>> +/* defines for device id register */
>> +#define QUADSPI_SID_REG 0x4
>> +#define QUADSPI_RDID_REG 0x8
>> +#define QUADSPI_ID_MASK 0x000000FF
>> +
>> +/*
>> + * QUADSPI_MEM_OP register offset
>> + *
>> + * The QUADSPI_MEM_OP register is used to do memory protect and erase operations
>> + *
>> + */
>> +#define QUADSPI_MEM_OP_REG 0xC
>> +
>> +#define QUADSPI_MEM_OP_CMD_MASK 0x00000003
>> +#define QUADSPI_MEM_OP_BULK_ERASE_CMD 0x00000001
>> +#define QUADSPI_MEM_OP_SECTOR_ERASE_CMD 0x00000002
>> +#define QUADSPI_MEM_OP_SECTOR_PROTECT_CMD 0x00000003
>> +#define QUADSPI_MEM_OP_SECTOR_VALUE_MASK 0x0003FF00
>> +#define QUADSPI_MEM_OP_SECTOR_PROTECT_VALUE_MASK 0x00001F00
>> +#define QUADSPI_MEM_OP_SECTOR_PROTECT_SHIFT 8
>> +/*
>> + * QUADSPI_ISR register offset
>> + *
>> + * The QUADSPI_ISR register is used to determine whether an invalid write or
>> + * erase operation trigerred an interrupt
>> + *
>> + */
>> +#define QUADSPI_ISR_REG 0x10
>> +
>> +#define QUADSPI_ISR_ILLEGAL_ERASE_MASK 0x00000001
>> +#define QUADSPI_ISR_ILLEGAL_WRITE_MASK 0x00000002
>> +
>> +/*
>> + * QUADSPI_IMR register offset
>> + *
>> + * The QUADSPI_IMR register is used to mask the invalid erase or the invalid
>> + * write interrupts.
>> + *
>> + */
>> +#define QUADSPI_IMR_REG 0x14
>> +#define QUADSPI_IMR_ILLEGAL_ERASE_MASK 0x00000001
>> +
>> +#define QUADSPI_IMR_ILLEGAL_WRITE_MASK 0x00000002
>> +
>> +#define QUADSPI_CHIP_SELECT_REG 0x18
>> +#define QUADSPI_CHIP_SELECT_MASK 0x00000007
>> +#define QUADSPI_CHIP_SELECT_0 0x00000001
>> +#define QUADSPI_CHIP_SELECT_1 0x00000002
>> +#define QUADSPI_CHIP_SELECT_2 0x00000004
>> +
>> +struct altera_quadspi_plat {
>> + void __iomem *csr_base;
>> + void __iomem *data_base;
>> + bool is_epcs;
>> + u32 num_flashes;
>> + struct device_node *np[MAX_NUM_FLASH_CHIP];
>> +};
>> +
>> +struct altera_quadspi {
>> + struct clk *clk;
>> + bool is_epcs;
>> + void __iomem *csr_base;
>> + void __iomem *data_base;
>> + u32 num_flashes;
>> + struct altera_quadspi_flash *flash[MAX_NUM_FLASH_CHIP];
>> +};
>> +
>> +struct altera_quadspi_flash {
>> + struct mtd_info mtd;
>> + struct spi_nor nor;
>> + void *priv;
>
> Does this really need to be 'void *'? Looks like it should be 'struct
> altera_quadspi *'.
>
>> +};
>> +
>> +struct flash_device {
>> + char *name;
>> + u8 opcode_id;
>> + u32 device_id;
>> +};
>> +
>> +#define FLASH_ID(_n, _opcode_id, _id) \
>> +{ \
>> + .name = (_n), \
>> + .opcode_id = (_opcode_id), \
>> + .device_id = (_id), \
>> +}
>> +
>> +static struct flash_device flash_devices[] = {
>> + FLASH_ID("epcq16-nonjedec", 2, 0x15),
>> + FLASH_ID("epcq32-nonjedec", 2, 0x16),
>> + FLASH_ID("epcq64-nonjedec", 2, 0x17),
>> + FLASH_ID("epcq128-nonjedec", 2, 0x18),
>> + FLASH_ID("epcq256-nonjedec", 2, 0x19),
>> + FLASH_ID("epcq512-nonjedec", 2, 0x20),
>> +
>> + FLASH_ID("epcs16-nonjedec", 1, 0x14),
>> + FLASH_ID("epcs64-nonjedec", 1, 0x16),
>> + FLASH_ID("epcs128-nonjedec", 1, 0x18),
>
> Rafal commented on this block, about *_OPCODE_ID.
>
>> +};
>> +
>> +static int altera_quadspi_write_reg(struct spi_nor *nor, u8 opcode, u8 *val,
>> + int len, int wr_en)
>> +{
>> + return 0;
>> +}
>> +
>> +static int altera_quadspi_read_reg(struct spi_nor *nor, u8 opcode, u8 *val,
>> + int len)
>> +{
>> + struct altera_quadspi_flash *flash = nor->priv;
>> + struct altera_quadspi *dev = flash->priv;
>> + u32 data = 0;
>> +
>> + switch (opcode) {
>> + case SPINOR_OP_RDSR:
>> + data = readl(dev->csr_base + QUADSPI_SR_REG);
>> + *val = (u8)data & QUADSPI_SR_MASK;
>> + break;
>> + case SPINOR_OP_RDID:
>> + /* opcode id */
>> + if (dev->is_epcs)
>> + data = readl(dev->csr_base + QUADSPI_SID_REG);
>> + else
>> + data = readl(dev->csr_base + QUADSPI_RDID_REG);
>> +
>> + *val = (u8)data & QUADSPI_ID_MASK; /* device id */
>> + break;
>> + default:
>> + *val = 0;
>> + break;
>
> Zero out the rest of val, since you're only filling the first byte?
>
>> + }
>> + return 0;
>> +}
>> +
>> +static int altera_quadspi_write_erase_check(struct spi_nor *nor,
>> + bool write_erase)
>> +{
>> + struct altera_quadspi_flash *flash = nor->priv;
>> + struct altera_quadspi *dev = flash->priv;
>> + u32 val;
>> + u32 mask;
>> +
>> + if (write_erase)
>> + mask = QUADSPI_ISR_ILLEGAL_WRITE_MASK;
>> + else
>> + mask = QUADSPI_ISR_ILLEGAL_ERASE_MASK;
>> +
>> + val = readl(dev->csr_base + QUADSPI_ISR_REG);
>> + if (val & mask) {
>> + dev_err(nor->dev,
>> + "write/erase failed, sector might be protected\n");
>> + /* clear this status for next use */
>> + writel(val, dev->csr_base + QUADSPI_ISR_REG);
>> + return -EIO;
>> + }
>> + return 0;
>> +}
>> +
>> +static int altera_quadspi_addr_to_sector(struct mtd_info *mtd, int offset)
>> +{
>> + if (mtd->erasesize_shift)
>> + return offset >> mtd->erasesize_shift;
>> + do_div(offset, mtd->erasesize);
>> + return offset;
>> +}
>> +
>> +static int altera_quadspi_erase(struct spi_nor *nor, loff_t offset)
>> +{
>> +
>> + struct altera_quadspi_flash *flash = nor->priv;
>> + struct altera_quadspi *dev = flash->priv;
>> + struct mtd_info *mtd = &flash->mtd;
>> + u32 val;
>> + int ret;
>> + int sector_value;
>> +
>> + sector_value = altera_quadspi_addr_to_sector(mtd, offset);
>> + /* sanity check that block_offset is a valid sector number */
>> + if (sector_value < 0)
>> + return -EINVAL;
>> +
>> + /* sector value should occupy bits 17:8 */
>> + val = (sector_value << 8) & QUADSPI_MEM_OP_SECTOR_VALUE_MASK;
>> +
>> + /* sector erase commands occupies lower 2 bits */
>> + val |= QUADSPI_MEM_OP_SECTOR_ERASE_CMD;
>> +
>> + /* write sector erase command to QUADSPI_MEM_OP register */
>> + writel(val, dev->csr_base + QUADSPI_MEM_OP_REG);
>> +
>> + ret = altera_quadspi_write_erase_check(nor, ERASE_CHECK);
>> + if (ret < 0) {
>> + dev_err(nor->dev, "illegal erase\n");
>> + return ret;
>> + }
>> + return 0;
>> +}
>> +
>> +static int altera_quadspi_read(struct spi_nor *nor, loff_t from, size_t len,
>> + size_t *retlen, u_char *buf)
>> +{
>> + struct altera_quadspi_flash *flash = nor->priv;
>> + struct altera_quadspi *dev = flash->priv;
>> +
>> + memcpy_fromio(buf, dev->data_base + from, len);
>> + *retlen = len;
>> +
>> + return 0;
>> +}
>> +
>> +static void altera_quadspi_write(struct spi_nor *nor, loff_t to, size_t len,
>> + size_t *retlen, const u_char *buf)
>> +{
>> + struct altera_quadspi_flash *flash = nor->priv;
>> + struct altera_quadspi *dev = flash->priv;
>> + int ret = 0;
>> +
>> + memcpy_toio(dev->data_base + to, buf, len);
>> + *retlen += len;
>> +
>> + /*
>> + * check whether write triggered a illegal write interrupt
>> + */
>> +
>> + ret = altera_quadspi_write_erase_check(nor, WRITE_CHECK);
>> + if (ret < 0)
>> + dev_err(nor->dev, "illegal write\n");
>> +
>> +
>> +}
>> +
>> +static int altera_quadspi_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)
>> +{
>> + struct altera_quadspi_flash *flash = nor->priv;
>> + struct altera_quadspi *dev = flash->priv;
>> + struct mtd_info *mtd = &flash->mtd;
>> + uint32_t offset = ofs;
>> + u32 sector_start, sector_end;
>> + u32 num_sectors;
>> + u32 mem_op;
>> + u32 sr_bp;
>> + u32 sr_tb;
>> +
>> + sector_start = offset;
>> + sector_end = altera_quadspi_addr_to_sector(mtd, offset + len);
>> + num_sectors = mtd->size;
>> + do_div(num_sectors, mtd->erasesize);
>> +
>> + dev_dbg(nor->dev, "%s: sector start is %u,sector end is %u\n",
>> + __func__, sector_start, sector_end);
>> +
>> + if (sector_start >= num_sectors / 2) {
>> + sr_bp = fls(num_sectors - 1 - sector_start) + 1;
>> + sr_tb = 0;
>> + } else if ((sector_end < num_sectors / 2) && ~dev->is_epcs) {
>> + sr_bp = fls(sector_end) + 1;
>> + sr_tb = 1;
>> + } else {
>> + sr_bp = 16;
>> + sr_tb = 0;
>> + }
>> +
>> + mem_op = (sr_tb << 12) | (sr_bp << 8);
>> + mem_op &= QUADSPI_MEM_OP_SECTOR_PROTECT_VALUE_MASK;
>> + mem_op |= QUADSPI_MEM_OP_SECTOR_PROTECT_CMD;
>> + writel(mem_op, dev->csr_base + QUADSPI_MEM_OP_REG);
>> +
>> + return 0;
>> +}
>> +
>> +static int altera_quadspi_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
>> +{
>> + struct altera_quadspi_flash *flash = nor->priv;
>> + struct altera_quadspi *dev = flash->priv;
>> + u32 mem_op;
>> +
>> + dev_dbg(nor->dev, "Unlock all protected area\n");
>> + mem_op = 0;
>> + mem_op &= QUADSPI_MEM_OP_SECTOR_PROTECT_VALUE_MASK;
>> + mem_op |= QUADSPI_MEM_OP_SECTOR_PROTECT_CMD;
>
> Can't the above 3 lines just be:
>
> mem_op = QUADSPI_MEM_OP_SECTOR_PROTECT_CMD;
>
> ?
>
>> + writel(mem_op, dev->csr_base + QUADSPI_MEM_OP_REG);
>> +
>> + return 0;
>> +}
>> +
>> +static void altera_quadspi_chip_select(struct altera_quadspi *dev, u32 bank)
>> +{
>> + u32 val = 0;
>> +
>> + switch (bank) {
>> + case 0:
>> + val = QUADSPI_CHIP_SELECT_0;
>> + break;
>> + case 1:
>> + val = QUADSPI_CHIP_SELECT_1;
>> + break;
>> + case 2:
>> + val = QUADSPI_CHIP_SELECT_2;
>> + break;
>> + default:
>> + return;
>> + }
>> + writel(val, dev->csr_base + QUADSPI_CHIP_SELECT_REG);
>> +}
>> +
>> +
>> +static int altera_quadspi_probe_config_dt(struct platform_device *pdev,
>> + struct device_node *np,
>> + struct altera_quadspi_plat *pdata)
>> +{
>> + struct device_node *pp = NULL;
>
> ^^ Is the NULL assignment necessary?
>
>> + struct resource *quadspi_res;
>> + int i = 0;
>> +
>> + pdata->is_epcs = of_property_read_bool(np, "is-epcs");
>> +
>> + quadspi_res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>> + "csr_base");
>> + pdata->csr_base = devm_ioremap_resource(&pdev->dev, quadspi_res);
>> + if (IS_ERR(pdata->csr_base)) {
>> + dev_err(&pdev->dev, "%s: ERROR: failed to map csr base\n",
>> + __func__);
>> + return PTR_ERR(pdata->csr_base);
>> + }
>> +
>> + quadspi_res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
>> + "data_base");
>> + pdata->data_base = devm_ioremap_resource(&pdev->dev, quadspi_res);
>> + if (IS_ERR(pdata->data_base)) {
>> + dev_err(&pdev->dev, "%s: ERROR: failed to map data base\n",
>> + __func__);
>> + return PTR_ERR(pdata->data_base);
>> + }
>> +
>> + /* Fill structs for each subnode (flash device) */
>> + for_each_available_child_of_node(np, pp) {
>> + /* Read bank id from DT */
>> + pdata->np[i] = pp;
>> + i++;
>> + }
>> + pdata->num_flashes = i;
>> + return 0;
>> +}
>> +
>> +static const char *get_flash_name(struct spi_nor *nor)
>> +{
>> + struct altera_quadspi_flash *flash = nor->priv;
>> + struct altera_quadspi *dev = flash->priv;
>> + int index;
>> + int ret;
>> + u8 id = 0;
>> + u8 opcode_id;
>> +
>> + opcode_id = dev->is_epcs ? EPCS_OPCODE_ID : EPCQ_OPCODE_ID;
>> + ret = nor->read_reg(nor, SPINOR_OP_RDID, &id, 1);
>> + if (ret)
>> + return NULL;
>> + for (index = 0; index < ARRAY_SIZE(flash_devices); index++) {
>> + if (flash_devices[index].device_id == id &&
>> + flash_devices[index].opcode_id == opcode_id)
>> + return flash_devices[index].name;
>> + }
>> +
>> + /* Memory chip is not listed and not supported */
>> + return NULL;
>> +}
>> +
>> +static int altera_quadspi_setup_banks(struct platform_device *pdev,
>> + u32 bank, struct device_node *np)
>> +{
>> + struct altera_quadspi *dev = platform_get_drvdata(pdev);
>> + struct mtd_part_parser_data ppdata = {};
>> + struct altera_quadspi_flash *flash;
>> + struct spi_nor *nor;
>> + int ret = 0;
>> + char modalias[40];
>> + const char *flash_name;
>> +
>> + altera_quadspi_chip_select(dev, bank);
>> +
>> + if (bank > dev->num_flashes - 1)
>> + return -EINVAL;
>
> Not a big deal, but wouldn't it make sense to put the 'bank > ...' check
> before the call to altera_quadspi_chip_select()?
>
>> +
>> + flash = devm_kzalloc(&pdev->dev, sizeof(*flash), GFP_KERNEL);
>> + if (!flash)
>> + return -ENOMEM;
>> +
>> + dev->flash[bank] = flash;
>> + nor = &flash->nor;
>> + nor->mtd = &flash->mtd;
>> + nor->dev = &pdev->dev;
>> + nor->priv = flash;
>> + flash->mtd.priv = nor;
>> + flash->priv = dev;
>> +
>> + /* spi nor framework*/
>> + nor->read_reg = altera_quadspi_read_reg;
>> + nor->write_reg = altera_quadspi_write_reg;
>> + nor->read = altera_quadspi_read;
>> + nor->write = altera_quadspi_write;
>> + nor->erase = altera_quadspi_erase;
>> + nor->flash_lock = altera_quadspi_lock;
>> + nor->flash_unlock = altera_quadspi_unlock;
>> +
>> + if (of_modalias_node(np, modalias, sizeof(modalias)) < 0)
>> + return -EINVAL;
>> +
>> + flash_name = get_flash_name(nor);
>> + if (flash_name == NULL)
>> + return -EINVAL;
>> +
>> + if (strcmp(flash_name, modalias) != 0) {
>> + dev_err(nor->dev,
>> + "flash name %s mismatch with device tree %s\n",
>> + flash_name, modalias);
>> + return -EINVAL;
>> + }
>> + ret = spi_nor_scan(nor, flash_name, SPI_NOR_QUAD);
>> + if (ret)
>> + return ret;
>> +
>> + ppdata.of_node = np;
>> +
>> + return mtd_device_parse_register(&flash->mtd, NULL, &ppdata, NULL, 0);
>> +}
>> +
>> +static int altera_quadspi_probe(struct platform_device *pdev)
>> +{
>> + struct device_node *np = pdev->dev.of_node;
>> + struct altera_quadspi_plat *pdata = NULL;
>
> The NULL assignment is superfluous.
>
>> + struct altera_quadspi *dev;
>> + int ret = 0;
>> + int i;
>> +
>> + if (!np) {
>> + ret = -ENODEV;
>> + dev_err(&pdev->dev, "no device found\n");
>> + goto err;
>> + }
>> +
>> + pdata = devm_kzalloc(&pdev->dev,
>> + sizeof(struct altera_quadspi_plat),
>> + GFP_KERNEL);
>
> It's not real clear why you're using this pdata struct at all. Are you
> planning to support non-DT platform devices, or is this going to be
> DT-only? (The check for "if (!np) { ... }" above looks like you're
> DT-only.)
>
> But anyway, this pdata struct is only used for the duration of the probe
> function, after which it is not used. It's true devm_* will take care of
> freeing it eventually, but wouldn't it make more sense to just free it
> up when you're done? e.g., put it on the stack instead (local variable)?
> Or just remove it entirely, and stash things directly into *dev and
> *flash.
>
>> +
>> + if (!pdata) {
>> + ret = -ENOMEM;
>> + goto err;
>> + }
>> +
>> + ret = altera_quadspi_probe_config_dt(pdev, np, pdata);
>> + if (ret) {
>> + ret = -ENODEV;
>> + dev_err(&pdev->dev, "probe fail\n");
>> + goto err;
>> + }
>> +
>> + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
>> + if (!dev) {
>> + ret = -ENOMEM;
>> + goto err;
>> + }
>> +
>> + dev->is_epcs = pdata->is_epcs;
>> + dev->csr_base = pdata->csr_base;
>> + dev->data_base = pdata->data_base;
>> +
>> + /* check number of flashes */
>> + dev->num_flashes = pdata->num_flashes;
>> + if (dev->num_flashes > MAX_NUM_FLASH_CHIP) {
>> + dev_err(&pdev->dev, "exceeding max number of flashes\n");
>> + dev->num_flashes = MAX_NUM_FLASH_CHIP;
>> + }
>> +
>> + /* check clock */
>> + dev->clk = devm_clk_get(&pdev->dev, NULL);
>> + if (IS_ERR(dev->clk)) {
>> + ret = PTR_ERR(dev->clk);
>> + goto err;
>> + }
>> + ret = clk_prepare_enable(dev->clk);
>> + if (ret)
>> + goto err;
>> +
>> + platform_set_drvdata(pdev, dev);
>> +
>> + /* loop for each flash which is connected to quadspi */
>> + for (i = 0; i < dev->num_flashes; i++) {
>> + ret = altera_quadspi_setup_banks(pdev, i, pdata->np[i]);
>> + if (ret) {
>> + dev_err(&pdev->dev, "bank setup failed\n");
>> + goto err_bank_setup;
>> + }
>> + }
>> +
>> + return 0;
>> +
>> +err_bank_setup:
>> + clk_disable_unprepare(dev->clk);
>> +err:
>> + return ret;
>> +}
>> +
>> +static int altera_quadspi_remove(struct platform_device *pdev)
>> +{
>> + struct altera_quadspi *dev;
>> + struct altera_quadspi_flash *flash;
>> + int ret, i;
>> +
>> + dev = platform_get_drvdata(pdev);
>> +
>> + /* clean up for all nor flash */
>> + for (i = 0; i < dev->num_flashes; i++) {
>> + flash = dev->flash[i];
>> + if (!flash)
>> + continue;
>> +
>> + /* clean up mtd stuff */
>> + ret = mtd_device_unregister(&flash->mtd);
>> + if (ret)
>> + dev_err(&pdev->dev, "error removing mtd\n");
>> + }
>> +
>> + clk_disable_unprepare(dev->clk);
>> +
>> + return 0;
>> +}
>> +
>> +static const struct of_device_id altera_quadspi_id_table[] = {
>> + { .compatible = "altr,quadspi-1.0" },
>> + {}
>> +};
>> +MODULE_DEVICE_TABLE(of, altera_quadspi_id_table);
>> +
>> +static struct platform_driver altera_quadspi_driver = {
>> + .driver = {
>> + .name = ALTERA_QUADSPI_RESOURCE_NAME,
>> + .bus = &platform_bus_type,
>
> ^^ You don't need that line. module_platform_driver() (specifically,
> __platform_driver_register()) takes care of this for you.
>
>> + .of_match_table = altera_quadspi_id_table,
>> + },
>> + .probe = altera_quadspi_probe,
>> + .remove = altera_quadspi_remove,
>> +};
>> +module_platform_driver(altera_quadspi_driver);
>> +
>> +MODULE_AUTHOR("Viet Nga Dao <vndao at altera.com>");
>> +MODULE_DESCRIPTION("Altera QuadSPI Driver");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
>> index 43bb552..ad0c274 100644
>> --- a/drivers/mtd/spi-nor/spi-nor.c
>> +++ b/drivers/mtd/spi-nor/spi-nor.c
>> @@ -683,6 +683,17 @@ static const struct spi_device_id spi_nor_ids[] = {
>> { "cat25c09", CAT25_INFO( 128, 8, 32, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) },
>> { "cat25c17", CAT25_INFO( 256, 8, 32, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) },
>> { "cat25128", CAT25_INFO(2048, 8, 64, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) },
>> +
>> + /* Altera EPCQ/EPCS Flashes */
>> + { "epcq16-nonjedec", INFO(0, 0, 0x10000, 32, 0) },
>> + { "epcq32-nonjedec", INFO(0, 0, 0x10000, 64, 0) },
>> + { "epcq64-nonjedec", INFO(0, 0, 0x10000, 128, 0) },
>> + { "epcq128-nonjedec", INFO(0, 0, 0x10000, 256, 0) },
>> + { "epcq256-nonjedec", INFO(0, 0, 0x10000, 512, 0) },
>> + { "epcq512-nonjedec", INFO(0, 0, 0x10000, 1024, 0) },
>> + { "epcs16-nonjedec", INFO(0, 0, 0x10000, 32, 0) },
>> + { "epcs64-nonjedec", INFO(0, 0, 0x10000, 128, 0) },
>> + { "epcs128-nonjedec", INFO(0, 0, 0x40000, 256, 0) },
>
> You probably should just drop the "-nonjedec" part. That will help you
> have a more sane DT binding. I realize you're imitating the
> "m25p80-nonjedec" entries that already exist, but I think those names
> exist mostly because there are otherwise-identical version of them that
> just don't support the READ ID command. Your parts are unique, and don't
> have corresponding JEDEC READ ID compatible versions.
>
> You could still include a comment above them, to note their origin, and
> how they don't support many traditional commands.
>
>> { },
>> };
>>
>
> Thanks,
> Brian
--
Nga
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