[RFC PATCH v2 08/14] mtd: nand: add sunxi NAND flash controller support
Boris BREZILLON
b.brezillon.dev at gmail.com
Thu Jan 30 06:22:25 EST 2014
On 29/01/2014 15:34, Boris BREZILLON wrote:
> Add support for the sunxi NAND Flash Controller (NFC).
>
> Signed-off-by: Boris BREZILLON <b.brezillon.dev at gmail.com>
> ---
> drivers/mtd/nand/Kconfig | 6 +
> drivers/mtd/nand/Makefile | 1 +
> drivers/mtd/nand/sunxi_nand.c | 744 +++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 751 insertions(+)
> create mode 100644 drivers/mtd/nand/sunxi_nand.c
>
> diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
> index 93ae6a6..784dd42 100644
> --- a/drivers/mtd/nand/Kconfig
> +++ b/drivers/mtd/nand/Kconfig
> @@ -510,4 +510,10 @@ config MTD_NAND_XWAY
> Enables support for NAND Flash chips on Lantiq XWAY SoCs. NAND is attached
> to the External Bus Unit (EBU).
>
> +config MTD_NAND_SUNXI
> + tristate "Support for NAND on Allwinner SoCs"
> + depends on ARCH_SUNXI
> + help
> + Enables support for NAND Flash chips on Allwinner SoCs.
> +
> endif # MTD_NAND
> diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
> index bbea7a6..e3b4a34 100644
> --- a/drivers/mtd/nand/Makefile
> +++ b/drivers/mtd/nand/Makefile
> @@ -49,5 +49,6 @@ obj-$(CONFIG_MTD_NAND_JZ4740) += jz4740_nand.o
> obj-$(CONFIG_MTD_NAND_GPMI_NAND) += gpmi-nand/
> obj-$(CONFIG_MTD_NAND_XWAY) += xway_nand.o
> obj-$(CONFIG_MTD_NAND_BCM47XXNFLASH) += bcm47xxnflash/
> +obj-$(CONFIG_MTD_NAND_SUNXI) += sunxi_nand.o
>
> nand-objs := nand_base.o nand_bbt.o
> diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
> new file mode 100644
> index 0000000..d3da810
> --- /dev/null
> +++ b/drivers/mtd/nand/sunxi_nand.c
> @@ -0,0 +1,744 @@
> +/*
> + * Copyright (C) 2013 Boris BREZILLON <b.brezillon.dev at gmail.com>
> + *
> + * Derived from:
> + * https://github.com/yuq/sunxi-nfc-mtd
> + * Copyright (C) 2013 Qiang Yu <yuq825 at gmail.com>
> + *
> + * https://github.com/hno/Allwinner-Info
> + * Copyright (C) 2013 Henrik Nordström <Henrik Nordström>
> + *
> + * Copyright (C) 2013 Dmitriy B. <rzk333 at gmail.com>
> + * Copyright (C) 2013 Sergey Lapin <slapin at ossfans.org>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that 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.
> + */
> +
> +#include <linux/dma-mapping.h>
> +#include <linux/slab.h>
> +#include <linux/module.h>
> +#include <linux/moduleparam.h>
> +#include <linux/platform_device.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_gpio.h>
> +#include <linux/of_mtd.h>
> +#include <linux/mtd/mtd.h>
> +#include <linux/mtd/nand.h>
> +#include <linux/mtd/partitions.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/dmaengine.h>
> +#include <linux/gpio.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +
> +#define NFC_REG_CTL 0x0000
> +#define NFC_REG_ST 0x0004
> +#define NFC_REG_INT 0x0008
> +#define NFC_REG_TIMING_CTL 0x000C
> +#define NFC_REG_TIMING_CFG 0x0010
> +#define NFC_REG_ADDR_LOW 0x0014
> +#define NFC_REG_ADDR_HIGH 0x0018
> +#define NFC_REG_SECTOR_NUM 0x001C
> +#define NFC_REG_CNT 0x0020
> +#define NFC_REG_CMD 0x0024
> +#define NFC_REG_RCMD_SET 0x0028
> +#define NFC_REG_WCMD_SET 0x002C
> +#define NFC_REG_IO_DATA 0x0030
> +#define NFC_REG_ECC_CTL 0x0034
> +#define NFC_REG_ECC_ST 0x0038
> +#define NFC_REG_DEBUG 0x003C
> +#define NFC_REG_ECC_CNT0 0x0040
> +#define NFC_REG_ECC_CNT1 0x0044
> +#define NFC_REG_ECC_CNT2 0x0048
> +#define NFC_REG_ECC_CNT3 0x004c
> +#define NFC_REG_USER_DATA_BASE 0x0050
> +#define NFC_REG_SPARE_AREA 0x00A0
> +#define NFC_RAM0_BASE 0x0400
> +#define NFC_RAM1_BASE 0x0800
> +
> +/*define bit use in NFC_CTL*/
> +#define NFC_EN (1 << 0)
> +#define NFC_RESET (1 << 1)
> +#define NFC_BUS_WIDYH (1 << 2)
> +#define NFC_RB_SEL (1 << 3)
> +#define NFC_CE_SEL (7 << 24)
> +#define NFC_CE_CTL (1 << 6)
> +#define NFC_CE_CTL1 (1 << 7)
> +#define NFC_PAGE_SIZE (0xf << 8)
> +#define NFC_SAM (1 << 12)
> +#define NFC_RAM_METHOD (1 << 14)
> +#define NFC_DEBUG_CTL (1 << 31)
> +
> +/*define bit use in NFC_ST*/
> +#define NFC_RB_B2R (1 << 0)
> +#define NFC_CMD_INT_FLAG (1 << 1)
> +#define NFC_DMA_INT_FLAG (1 << 2)
> +#define NFC_CMD_FIFO_STATUS (1 << 3)
> +#define NFC_STA (1 << 4)
> +#define NFC_NATCH_INT_FLAG (1 << 5)
> +#define NFC_RB_STATE0 (1 << 8)
> +#define NFC_RB_STATE1 (1 << 9)
> +#define NFC_RB_STATE2 (1 << 10)
> +#define NFC_RB_STATE3 (1 << 11)
> +
> +/*define bit use in NFC_INT*/
> +#define NFC_B2R_INT_ENABLE (1 << 0)
> +#define NFC_CMD_INT_ENABLE (1 << 1)
> +#define NFC_DMA_INT_ENABLE (1 << 2)
> +#define NFC_INT_MASK (NFC_B2R_INT_ENABLE | \
> + NFC_CMD_INT_ENABLE | \
> + NFC_DMA_INT_ENABLE)
> +
> +
> +/*define bit use in NFC_CMD*/
> +#define NFC_CMD_LOW_BYTE (0xff << 0)
> +#define NFC_CMD_HIGH_BYTE (0xff << 8)
> +#define NFC_ADR_NUM (0x7 << 16)
> +#define NFC_SEND_ADR (1 << 19)
> +#define NFC_ACCESS_DIR (1 << 20)
> +#define NFC_DATA_TRANS (1 << 21)
> +#define NFC_SEND_CMD1 (1 << 22)
> +#define NFC_WAIT_FLAG (1 << 23)
> +#define NFC_SEND_CMD2 (1 << 24)
> +#define NFC_SEQ (1 << 25)
> +#define NFC_DATA_SWAP_METHOD (1 << 26)
> +#define NFC_ROW_AUTO_INC (1 << 27)
> +#define NFC_SEND_CMD3 (1 << 28)
> +#define NFC_SEND_CMD4 (1 << 29)
> +#define NFC_CMD_TYPE (3 << 30)
> +
> +/* define bit use in NFC_RCMD_SET*/
> +#define NFC_READ_CMD (0xff << 0)
> +#define NFC_RANDOM_READ_CMD0 (0xff << 8)
> +#define NFC_RANDOM_READ_CMD1 (0xff << 16)
> +
> +/*define bit use in NFC_WCMD_SET*/
> +#define NFC_PROGRAM_CMD (0xff << 0)
> +#define NFC_RANDOM_WRITE_CMD (0xff << 8)
> +#define NFC_READ_CMD0 (0xff << 16)
> +#define NFC_READ_CMD1 (0xff << 24)
> +
> +/*define bit use in NFC_ECC_CTL*/
> +#define NFC_ECC_EN (1 << 0)
> +#define NFC_ECC_PIPELINE (1 << 3)
> +#define NFC_ECC_EXCEPTION (1 << 4)
> +#define NFC_ECC_BLOCK_SIZE (1 << 5)
> +#define NFC_RANDOM_EN (1 << 9)
> +#define NFC_RANDOM_DIRECTION (1 << 10)
> +#define NFC_ECC_MODE_SHIFT 12
> +#define NFC_ECC_MODE (0xf << NFC_ECC_MODE_SHIFT)
> +#define NFC_RANDOM_SEED (0x7fff << 16)
> +
> +
> +
> +enum sunxi_nand_rb_type {
> + RB_NONE,
> + RB_NATIVE,
> + RB_GPIO,
> +};
> +
> +struct sunxi_nand_rb {
> + enum sunxi_nand_rb_type type;
> + union {
> + int gpio;
> + int nativeid;
> + } info;
> +};
> +
> +struct sunxi_nand_chip_sel {
> + u8 cs;
> + struct sunxi_nand_rb rb;
> +};
> +
> +#define DEFAULT_NAME_FORMAT "nand@%d"
> +#define MAX_NAME_SIZE (sizeof("nand@") + 2)
> +
> +struct sunxi_nand_chip {
> + struct list_head node;
> + struct nand_chip nand;
> + struct mtd_info mtd;
> + char default_name[MAX_NAME_SIZE];
> + unsigned long clk_rate;
> + int selected;
> + int nsels;
> + struct sunxi_nand_chip_sel sels[0];
> +};
> +
> +static inline struct sunxi_nand_chip *to_sunxi_nand(struct mtd_info *mtd)
> +{
> + return container_of(mtd, struct sunxi_nand_chip, mtd);
> +}
> +
> +struct sunxi_nfc {
> + struct nand_hw_control controller;
> + void __iomem *regs;
> + int irq;
> + struct clk *ahb_clk;
> + struct clk *sclk;
> + unsigned long assigned_cs;
> + unsigned long clk_rate;
> + struct list_head chips;
> + struct completion complete;
> +};
> +
> +static inline struct sunxi_nfc *to_sunxi_nfc(struct nand_hw_control *ctrl)
> +{
> + return container_of(ctrl, struct sunxi_nfc, controller);
> +}
> +
> +static irqreturn_t sunxi_nfc_interrupt(int irq, void *dev_id)
> +{
> + struct sunxi_nfc *nfc = dev_id;
> + u32 st = readl(nfc->regs + NFC_REG_ST);
> + u32 ien = readl(nfc->regs + NFC_REG_INT);
> +
> + if (!(ien & st))
> + return IRQ_NONE;
> +
> + if ((ien & st) == ien)
> + complete(&nfc->complete);
> +
> + writel(st & NFC_INT_MASK, nfc->regs + NFC_REG_ST);
> + writel(~st & ien & NFC_INT_MASK, nfc->regs + NFC_REG_INT);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int sunxi_nfc_wait_int(struct sunxi_nfc *nfc, u32 flags,
> + unsigned int timeout_ms)
> +{
> + init_completion(&nfc->complete);
> +
> + writel(flags, nfc->regs + NFC_REG_INT);
> + if (!timeout_ms)
> + wait_for_completion(&nfc->complete);
> + else if (!wait_for_completion_timeout(&nfc->complete,
> + msecs_to_jiffies(timeout_ms)))
> + return -ETIMEDOUT;
> +
> + return 0;
> +}
> +
> +static int sunxi_nfc_dev_ready(struct mtd_info *mtd)
> +{
> + struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(mtd);
> + struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
> + struct sunxi_nand_rb *rb;
> + unsigned long timeo = (sunxi_nand->nand.state == FL_ERASING ? 400 : 20);
> + int ret;
> +
> + if (sunxi_nand->selected < 0)
> + return 0;
> +
> + rb = &sunxi_nand->sels[sunxi_nand->selected].rb;
> +
> + switch (rb->type) {
> + case RB_NATIVE:
> + ret = !!(readl(nfc->regs + NFC_REG_ST) &
> + (NFC_RB_STATE0 << rb->info.nativeid));
> + if (ret)
> + break;
> +
> + sunxi_nfc_wait_int(nfc, NFC_RB_B2R, timeo);
> + ret = !!(readl(nfc->regs + NFC_REG_ST) &
> + (NFC_RB_STATE0 << rb->info.nativeid));
> + break;
> + case RB_GPIO:
> + ret = gpio_get_value(rb->info.gpio);
> + break;
> + case RB_NONE:
> + default:
> + ret = 0;
> + dev_err(&mtd->dev, "cannot check R/B NAND status!");
> + break;
> + }
> +
> + return ret;
> +}
> +
> +static void sunxi_nfc_select_chip(struct mtd_info *mtd, int chip)
> +{
> + struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(mtd);
> + struct nand_chip *nand = &sunxi_nand->nand;
> + struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
> + struct sunxi_nand_chip_sel *sel;
> + u32 ctl;
> +
> + if (chip > 0 && chip >= sunxi_nand->nsels)
> + return;
> +
> + if (chip == sunxi_nand->selected)
> + return;
> +
> + ctl = readl(nfc->regs + NFC_REG_CTL) &
> + ~(NFC_CE_SEL | NFC_RB_SEL | NFC_EN);
> +
> + if (chip >= 0) {
> + sel = &sunxi_nand->sels[chip];
> +
> + ctl |= (sel->cs << 24) | NFC_EN |
> + (((nand->page_shift - 10) & 0xf) << 8);
> + if (sel->rb.type == RB_NONE) {
> + nand->dev_ready = NULL;
> + } else {
> + nand->dev_ready = sunxi_nfc_dev_ready;
> + if (sel->rb.type == RB_NATIVE)
> + ctl |= (sel->rb.info.nativeid << 3);
> + }
> +
> + writel(mtd->writesize, nfc->regs + NFC_REG_SPARE_AREA);
> +
> + if (nfc->clk_rate != sunxi_nand->clk_rate) {
> + clk_set_rate(nfc->sclk, sunxi_nand->clk_rate);
> + nfc->clk_rate = sunxi_nand->clk_rate;
> + }
> + }
> +
> + writel(ctl, nfc->regs + NFC_REG_CTL);
> +
> + sunxi_nand->selected = chip;
> +}
> +
> +static void sunxi_nfc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
> +{
> + struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(mtd);
> + struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
> + int cnt;
> + int offs = 0;
> + u32 tmp;
> +
> + while (len > offs) {
> + cnt = len - offs;
> + if (cnt > 1024)
> + cnt = 1024;
> +
> + while ((readl(nfc->regs + NFC_REG_ST) & NFC_CMD_FIFO_STATUS))
> + ;
> + writel(cnt, nfc->regs + NFC_REG_CNT);
> + tmp = NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD;
> + writel(tmp, nfc->regs + NFC_REG_CMD);
> + sunxi_nfc_wait_int(nfc, NFC_CMD_INT_FLAG, 0);
> + if (buf)
> + memcpy_fromio(buf + offs, nfc->regs + NFC_RAM0_BASE,
> + cnt);
> + offs += cnt;
> + }
> +}
> +
> +static void sunxi_nfc_write_buf(struct mtd_info *mtd, const uint8_t *buf,
> + int len)
> +{
> + struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(mtd);
> + struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
> + int cnt;
> + int offs = 0;
> + u32 tmp;
> +
> + while (len > offs) {
> + cnt = len - offs;
> + if (cnt > 1024)
> + cnt = 1024;
> +
> + while ((readl(nfc->regs + NFC_REG_ST) & NFC_CMD_FIFO_STATUS))
> + ;
> + writel(cnt, nfc->regs + NFC_REG_CNT);
> + memcpy_toio(nfc->regs + NFC_RAM0_BASE, buf + offs, cnt);
> + tmp = NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD |
> + NFC_ACCESS_DIR;
> + writel(tmp, nfc->regs + NFC_REG_CMD);
> + sunxi_nfc_wait_int(nfc, NFC_CMD_INT_FLAG, 0);
> + offs += cnt;
> + }
> +}
> +
> +static uint8_t sunxi_nfc_read_byte(struct mtd_info *mtd)
> +{
> + uint8_t ret;
> +
> + sunxi_nfc_read_buf(mtd, &ret, 1);
> +
> + return ret;
> +}
> +
> +static void sunxi_nfc_cmd_ctrl(struct mtd_info *mtd, int dat,
> + unsigned int ctrl)
> +{
> + struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(mtd);
> + struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
> + u32 tmp;
> +
> + while ((readl(nfc->regs + NFC_REG_ST) & NFC_CMD_FIFO_STATUS))
> + ;
> +
> + if (ctrl & NAND_CTRL_CHANGE) {
> + tmp = readl(nfc->regs + NFC_REG_CTL);
> + if (ctrl & NAND_NCE)
> + tmp |= NFC_CE_CTL;
> + else
> + tmp &= ~NFC_CE_CTL;
> + writel(tmp, nfc->regs + NFC_REG_CTL);
> + }
> +
> + if (dat == NAND_CMD_NONE)
> + return;
> +
> + if (ctrl & NAND_CLE) {
> + writel(NFC_SEND_CMD1 | dat, nfc->regs + NFC_REG_CMD);
> + } else {
> + writel(dat, nfc->regs + NFC_REG_ADDR_LOW);
> + writel(NFC_SEND_ADR, nfc->regs + NFC_REG_CMD);
> + }
> +
> + sunxi_nfc_wait_int(nfc, NFC_CMD_INT_FLAG, 0);
> +}
> +
> +static int sunxi_nand_chip_init_timings(struct sunxi_nand_chip *chip,
> + struct device_node *np)
> +{
> + const struct nand_sdr_timings *timings;
> + u32 min_clk_period = 0;
> + int ret;
> +
> + ret = onfi_get_async_timing_mode(&chip->nand);
> + if (ret == ONFI_TIMING_MODE_UNKNOWN) {
> + ret = of_get_nand_onfi_timing_mode(np);
> + if (ret < 0)
> + return ret;
> + }
> +
> + ret = fls(ret);
> + if (!ret)
> + return -EINVAL;
> +
> + timings = onfi_async_timing_mode_to_sdr_timings(ret - 1);
> + if (IS_ERR(timings))
> + return PTR_ERR(timings);
> +
> + /* NFC timings defined in Allwinner Datasheets */
> +
> + /* T1 <=> tCLS */
> + if (timings->tCLS_min > min_clk_period)
> + min_clk_period = timings->tCLS_min;
> +
> + /* T2 <=> tCLH */
> + if (timings->tCLH_min > min_clk_period)
> + min_clk_period = timings->tCLH_min;
> +
> + /* T3 <=> tCS */
> + if (timings->tCS_min > min_clk_period)
> + min_clk_period = timings->tCS_min;
> +
> + /* T4 <=> tCH */
> + if (timings->tCH_min > min_clk_period)
> + min_clk_period = timings->tCH_min;
> +
> + /* T5 <=> tWP */
> + if (timings->tWP_min > min_clk_period)
> + min_clk_period = timings->tWP_min;
> +
> + /* T6 <=> tWH */
> + if (timings->tWH_min > min_clk_period)
> + min_clk_period = timings->tWH_min;
> +
> + /* T7 <=> tALS */
> + if (timings->tALS_min > min_clk_period)
> + min_clk_period = timings->tALS_min;
> +
> + /* T8 <=> tDS */
> + if (timings->tDS_min > min_clk_period)
> + min_clk_period = timings->tDS_min;
> +
> + /* T9 <=> tDH */
> + if (timings->tDH_min > min_clk_period)
> + min_clk_period = timings->tDH_min;
> +
> + /* T10 <=> tRR */
> + if (timings->tRR_min > (min_clk_period * 3))
> + min_clk_period = (timings->tRR_min + 2) / 3;
> +
> + /* T11 <=> tALH */
> + if (timings->tALH_min > min_clk_period)
> + min_clk_period = timings->tALH_min;
> +
> + /* T12 <=> tRP */
> + if (timings->tRP_min > min_clk_period)
> + min_clk_period = timings->tRP_min;
> +
> + /* T13 <=> tREH */
> + if (timings->tREH_min > min_clk_period)
> + min_clk_period = timings->tREH_min;
> +
> + /* T14 <=> tRC */
> + if (timings->tRC_min > (min_clk_period * 2))
> + min_clk_period = (timings->tRC_min + 1) / 2;
> +
> + /* T15 <=> tWC */
> + if (timings->tWC_min > (min_clk_period * 2))
> + min_clk_period = (timings->tWC_min + 1) / 2;
> +
> +
> + /* min_clk_period = (NAND-clk-period * 2) */
> + if (!min_clk_period) {
> + chip->clk_rate = 20000000;
> + } else {
> + min_clk_period /= 1000;
> + if (!min_clk_period)
> + min_clk_period = 1;
> + chip->clk_rate = (2 * 1000000000) / min_clk_period;
> + }
> +
> + /* TODO: configure T16-T19 */
> +
> + return 0;
> +}
> +
> +static int sunxi_nand_chip_init(struct device *dev, struct sunxi_nfc *nfc,
> + struct device_node *np)
> +{
> + struct sunxi_nand_chip *chip;
> + struct mtd_part_parser_data ppdata;
> + struct mtd_info *mtd;
> + struct nand_chip *nand;
> + u32 strength;
> + u32 blk_size;
> + int nsels;
> + int ret;
> + int i;
> + u32 tmp;
> +
> + if (!of_get_property(np, "reg", &nsels))
> + return -EINVAL;
> +
> + nsels /= sizeof(u32);
> + if (!nsels)
> + return -EINVAL;
> +
> + chip = devm_kzalloc(dev,
> + sizeof(*chip) +
> + (nsels * sizeof(struct sunxi_nand_chip_sel)),
> + GFP_KERNEL);
> + if (!chip)
> + return -ENOMEM;
> +
> + chip->nsels = nsels;
> + chip->selected = -1;
> +
> + for (i = 0; i < nsels; i++) {
> + ret = of_property_read_u32_index(np, "reg", i, &tmp);
> + if (ret)
> + return ret;
> +
> + if (tmp > 7)
> + return -EINVAL;
> +
> + if (test_and_set_bit(tmp, &nfc->assigned_cs))
> + return -EINVAL;
> +
> + chip->sels[i].cs = tmp;
> +
> + if (!of_property_read_u32_index(np, "allwinner,rb", i, &tmp) &&
> + tmp < 2) {
> + chip->sels[i].rb.type = RB_NATIVE;
> + chip->sels[i].rb.info.nativeid = tmp;
> + } else {
> + ret = of_get_named_gpio(np, "rb-gpios", i);
> + if (ret >= 0) {
> + chip->sels[i].rb.type = RB_GPIO;
> + chip->sels[i].rb.info.gpio = tmp;
> + ret = devm_gpio_request(dev, tmp, "nand-rb");
> + if (ret)
> + return ret;
While testing the GPIO handling of R/B state, I found 2 bugs:
- the GPIO number is stored in ret not tmp
- we need to configure the GPIO as an input
Here's a patch fixing these bugs:
diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index 7e1cefc..41fb3b8 100644
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -814,11 +814,16 @@ static int sunxi_nand_chip_init(struct device
*dev, struct sunxi_nfc *nfc,
} else {
ret = of_get_named_gpio(np, "rb-gpios", i);
if (ret >= 0) {
+ tmp = ret;
chip->sels[i].rb.type = RB_GPIO;
chip->sels[i].rb.info.gpio = tmp;
ret = devm_gpio_request(dev, tmp,
"nand-rb");
if (ret)
return ret;
+
+ ret = gpio_direction_input(tmp);
+ if (ret)
+ return ret;
} else {
chip->sels[i].rb.type = RB_NONE;
}
I'll fix it for the next version.
> + } else {
> + chip->sels[i].rb.type = RB_NONE;
> + }
> + }
> + }
> +
> + ret = sunxi_nand_chip_init_timings(chip, np);
> + if (ret)
> + return ret;
> +
> + nand = &chip->nand;
> + nand->controller = &nfc->controller;
> + nand->select_chip = sunxi_nfc_select_chip;
> + nand->cmd_ctrl = sunxi_nfc_cmd_ctrl;
> + nand->read_buf = sunxi_nfc_read_buf;
> + nand->write_buf = sunxi_nfc_write_buf;
> + nand->read_byte = sunxi_nfc_read_byte;
> +
> + nand->ecc.mode = of_get_nand_ecc_mode(np);
> + if (of_get_nand_on_flash_bbt(np))
> + nand->bbt_options |= NAND_BBT_USE_FLASH;
> +
> + mtd = &chip->mtd;
> + mtd->priv = nand;
> + mtd->owner = THIS_MODULE;
> +
> + ret = nand_scan_ident(mtd, nsels, NULL);
> + if (ret)
> + return ret;
> +
> + if (nand->ecc.mode == NAND_ECC_SOFT_BCH) {
> + if (!of_get_nand_ecc_level(np, &strength, &blk_size)) {
> + nand->ecc_step_ds = blk_size;
> + nand->ecc_strength_ds = strength;
> + }
> +
> + nand->ecc.size = nand->ecc_step_ds;
> + nand->ecc.bytes = (((nand->ecc_strength_ds *
> + fls(8 * nand->ecc_step_ds)) + 7) / 8);
> + }
> +
> + ret = nand_scan_tail(mtd);
> + if (ret)
> + return ret;
> +
> + if (of_property_read_string(np, "nand-name", &mtd->name)) {
> + snprintf(chip->default_name, MAX_NAME_SIZE,
> + DEFAULT_NAME_FORMAT, chip->sels[i].cs);
> + mtd->name = chip->default_name;
> + }
> +
> + ppdata.of_node = np;
> + ret = mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0);
> + if (!ret)
> + return ret;
> +
> + list_add_tail(&chip->node, &nfc->chips);
> +
> + return 0;
> +}
> +
> +static int sunxi_nand_chips_init(struct device *dev, struct sunxi_nfc *nfc)
> +{
> + struct device_node *np = dev->of_node;
> + struct device_node *nand_np;
> + int nchips = of_get_child_count(np);
> + int ret;
> +
> + if (nchips > 8)
> + return -EINVAL;
> +
> + for_each_child_of_node(np, nand_np) {
> + ret = sunxi_nand_chip_init(dev, nfc, nand_np);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int sunxi_nfc_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct resource *r;
> + struct sunxi_nfc *nfc;
> + int ret;
> +
> + nfc = devm_kzalloc(dev, sizeof(*nfc), GFP_KERNEL);
> + if (!nfc) {
> + dev_err(dev, "failed to allocate NFC struct\n");
> + return -ENOMEM;
> + }
> +
> + spin_lock_init(&nfc->controller.lock);
> + init_waitqueue_head(&nfc->controller.wq);
> + INIT_LIST_HEAD(&nfc->chips);
> +
> + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + nfc->regs = devm_ioremap_resource(dev, r);
> + if (IS_ERR(nfc->regs)) {
> + dev_err(dev, "failed to remap iomem\n");
> + return PTR_ERR(nfc->regs);
> + }
> +
> + nfc->irq = platform_get_irq(pdev, 0);
> + if (nfc->irq < 0) {
> + dev_err(dev, "failed to retrieve irq\n");
> + return nfc->irq;
> + }
> +
> + nfc->ahb_clk = devm_clk_get(dev, "ahb_clk");
> + if (IS_ERR(nfc->ahb_clk)) {
> + dev_err(dev, "failed to retrieve ahb_clk\n");
> + return PTR_ERR(nfc->ahb_clk);
> + }
> +
> + ret = clk_prepare_enable(nfc->ahb_clk);
> + if (ret)
> + return ret;
> +
> + nfc->sclk = devm_clk_get(dev, "sclk");
> + if (IS_ERR(nfc->sclk)) {
> + dev_err(dev, "failed to retrieve nand_clk\n");
> + ret = PTR_ERR(nfc->sclk);
> + goto out_ahb_clk_unprepare;
> + }
> +
> + ret = clk_prepare_enable(nfc->sclk);
> + if (ret)
> + goto out_ahb_clk_unprepare;
> +
> + /* Reset NFC */
> + writel(readl(nfc->regs + NFC_REG_CTL) | NFC_RESET,
> + nfc->regs + NFC_REG_CTL);
> + while (readl(nfc->regs + NFC_REG_CTL) & NFC_RESET)
> + ;
> +
> + writel(0, nfc->regs + NFC_REG_INT);
> + ret = devm_request_irq(dev, nfc->irq, sunxi_nfc_interrupt,
> + 0, "sunxi-nand", nfc);
> + if (ret)
> + goto out_sclk_unprepare;
> +
> + platform_set_drvdata(pdev, nfc);
> +
> + writel(0x100, nfc->regs + NFC_REG_TIMING_CTL);
> + writel(0x7ff, nfc->regs + NFC_REG_TIMING_CFG);
> +
> + ret = sunxi_nand_chips_init(dev, nfc);
> + if (ret) {
> + dev_err(dev, "failed to init nand chips\n");
> + goto out_sclk_unprepare;
> + }
> +
> + return 0;
> +
> +out_sclk_unprepare:
> + clk_disable_unprepare(nfc->sclk);
> +out_ahb_clk_unprepare:
> + clk_disable_unprepare(nfc->ahb_clk);
> +
> + return ret;
> +}
> +
> +static const struct of_device_id sunxi_nfc_ids[] = {
> + { .compatible = "allwinner,sun4i-nand" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, sunxi_nfc_ids);
> +
> +static struct platform_driver sunxi_nfc_driver = {
> + .driver = {
> + .name = "sunxi_nand",
> + .owner = THIS_MODULE,
> + .of_match_table = of_match_ptr(sunxi_nfc_ids),
> + },
> + .probe = sunxi_nfc_probe,
> +};
> +module_platform_driver(sunxi_nfc_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Boris BREZILLON");
> +MODULE_DESCRIPTION("Allwinner NAND Flash Controller driver");
> +MODULE_ALIAS("platform:sunxi_nfc");
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