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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /drivers/mtd/nand/raw/ams-delta.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/mtd/nand/raw/ams-delta.c')
-rw-r--r-- | drivers/mtd/nand/raw/ams-delta.c | 449 |
1 files changed, 449 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/ams-delta.c b/drivers/mtd/nand/raw/ams-delta.c new file mode 100644 index 000000000..13de39aa3 --- /dev/null +++ b/drivers/mtd/nand/raw/ams-delta.c @@ -0,0 +1,449 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2006 Jonathan McDowell <noodles@earth.li> + * + * Derived from drivers/mtd/nand/toto.c (removed in v2.6.28) + * Copyright (c) 2003 Texas Instruments + * Copyright (c) 2002 Thomas Gleixner <tgxl@linutronix.de> + * + * Converted to platform driver by Janusz Krzysztofik <jkrzyszt@tis.icnet.pl> + * Partially stolen from plat_nand.c + * + * Overview: + * This is a device driver for the NAND flash device found on the + * Amstrad E3 (Delta). + */ + +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/nand-gpio.h> +#include <linux/mtd/rawnand.h> +#include <linux/mtd/partitions.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/sizes.h> + +/* + * MTD structure for E3 (Delta) + */ +struct gpio_nand { + struct nand_controller base; + struct nand_chip nand_chip; + struct gpio_desc *gpiod_rdy; + struct gpio_desc *gpiod_nce; + struct gpio_desc *gpiod_nre; + struct gpio_desc *gpiod_nwp; + struct gpio_desc *gpiod_nwe; + struct gpio_desc *gpiod_ale; + struct gpio_desc *gpiod_cle; + struct gpio_descs *data_gpiods; + bool data_in; + unsigned int tRP; + unsigned int tWP; + u8 (*io_read)(struct gpio_nand *this); + void (*io_write)(struct gpio_nand *this, u8 byte); +}; + +static void gpio_nand_write_commit(struct gpio_nand *priv) +{ + gpiod_set_value(priv->gpiod_nwe, 1); + ndelay(priv->tWP); + gpiod_set_value(priv->gpiod_nwe, 0); +} + +static void gpio_nand_io_write(struct gpio_nand *priv, u8 byte) +{ + struct gpio_descs *data_gpiods = priv->data_gpiods; + DECLARE_BITMAP(values, BITS_PER_TYPE(byte)) = { byte, }; + + gpiod_set_raw_array_value(data_gpiods->ndescs, data_gpiods->desc, + data_gpiods->info, values); + + gpio_nand_write_commit(priv); +} + +static void gpio_nand_dir_output(struct gpio_nand *priv, u8 byte) +{ + struct gpio_descs *data_gpiods = priv->data_gpiods; + DECLARE_BITMAP(values, BITS_PER_TYPE(byte)) = { byte, }; + int i; + + for (i = 0; i < data_gpiods->ndescs; i++) + gpiod_direction_output_raw(data_gpiods->desc[i], + test_bit(i, values)); + + gpio_nand_write_commit(priv); + + priv->data_in = false; +} + +static u8 gpio_nand_io_read(struct gpio_nand *priv) +{ + u8 res; + struct gpio_descs *data_gpiods = priv->data_gpiods; + DECLARE_BITMAP(values, BITS_PER_TYPE(res)) = { 0, }; + + gpiod_set_value(priv->gpiod_nre, 1); + ndelay(priv->tRP); + + gpiod_get_raw_array_value(data_gpiods->ndescs, data_gpiods->desc, + data_gpiods->info, values); + + gpiod_set_value(priv->gpiod_nre, 0); + + res = values[0]; + return res; +} + +static void gpio_nand_dir_input(struct gpio_nand *priv) +{ + struct gpio_descs *data_gpiods = priv->data_gpiods; + int i; + + for (i = 0; i < data_gpiods->ndescs; i++) + gpiod_direction_input(data_gpiods->desc[i]); + + priv->data_in = true; +} + +static void gpio_nand_write_buf(struct gpio_nand *priv, const u8 *buf, int len) +{ + int i = 0; + + if (len > 0 && priv->data_in) + gpio_nand_dir_output(priv, buf[i++]); + + while (i < len) + priv->io_write(priv, buf[i++]); +} + +static void gpio_nand_read_buf(struct gpio_nand *priv, u8 *buf, int len) +{ + int i; + + if (priv->data_gpiods && !priv->data_in) + gpio_nand_dir_input(priv); + + for (i = 0; i < len; i++) + buf[i] = priv->io_read(priv); +} + +static void gpio_nand_ctrl_cs(struct gpio_nand *priv, bool assert) +{ + gpiod_set_value(priv->gpiod_nce, assert); +} + +static int gpio_nand_exec_op(struct nand_chip *this, + const struct nand_operation *op, bool check_only) +{ + struct gpio_nand *priv = nand_get_controller_data(this); + const struct nand_op_instr *instr; + int ret = 0; + + if (check_only) + return 0; + + gpio_nand_ctrl_cs(priv, 1); + + for (instr = op->instrs; instr < op->instrs + op->ninstrs; instr++) { + switch (instr->type) { + case NAND_OP_CMD_INSTR: + gpiod_set_value(priv->gpiod_cle, 1); + gpio_nand_write_buf(priv, &instr->ctx.cmd.opcode, 1); + gpiod_set_value(priv->gpiod_cle, 0); + break; + + case NAND_OP_ADDR_INSTR: + gpiod_set_value(priv->gpiod_ale, 1); + gpio_nand_write_buf(priv, instr->ctx.addr.addrs, + instr->ctx.addr.naddrs); + gpiod_set_value(priv->gpiod_ale, 0); + break; + + case NAND_OP_DATA_IN_INSTR: + gpio_nand_read_buf(priv, instr->ctx.data.buf.in, + instr->ctx.data.len); + break; + + case NAND_OP_DATA_OUT_INSTR: + gpio_nand_write_buf(priv, instr->ctx.data.buf.out, + instr->ctx.data.len); + break; + + case NAND_OP_WAITRDY_INSTR: + ret = priv->gpiod_rdy ? + nand_gpio_waitrdy(this, priv->gpiod_rdy, + instr->ctx.waitrdy.timeout_ms) : + nand_soft_waitrdy(this, + instr->ctx.waitrdy.timeout_ms); + break; + } + + if (ret) + break; + } + + gpio_nand_ctrl_cs(priv, 0); + + return ret; +} + +static int gpio_nand_setup_interface(struct nand_chip *this, int csline, + const struct nand_interface_config *cf) +{ + struct gpio_nand *priv = nand_get_controller_data(this); + const struct nand_sdr_timings *sdr = nand_get_sdr_timings(cf); + struct device *dev = &nand_to_mtd(this)->dev; + + if (IS_ERR(sdr)) + return PTR_ERR(sdr); + + if (csline == NAND_DATA_IFACE_CHECK_ONLY) + return 0; + + if (priv->gpiod_nre) { + priv->tRP = DIV_ROUND_UP(sdr->tRP_min, 1000); + dev_dbg(dev, "using %u ns read pulse width\n", priv->tRP); + } + + priv->tWP = DIV_ROUND_UP(sdr->tWP_min, 1000); + dev_dbg(dev, "using %u ns write pulse width\n", priv->tWP); + + return 0; +} + +static int gpio_nand_attach_chip(struct nand_chip *chip) +{ + if (chip->ecc.engine_type == NAND_ECC_ENGINE_TYPE_SOFT && + chip->ecc.algo == NAND_ECC_ALGO_UNKNOWN) + chip->ecc.algo = NAND_ECC_ALGO_HAMMING; + + return 0; +} + +static const struct nand_controller_ops gpio_nand_ops = { + .exec_op = gpio_nand_exec_op, + .attach_chip = gpio_nand_attach_chip, + .setup_interface = gpio_nand_setup_interface, +}; + +/* + * Main initialization routine + */ +static int gpio_nand_probe(struct platform_device *pdev) +{ + struct gpio_nand_platdata *pdata = dev_get_platdata(&pdev->dev); + const struct mtd_partition *partitions = NULL; + int num_partitions = 0; + struct gpio_nand *priv; + struct nand_chip *this; + struct mtd_info *mtd; + int (*probe)(struct platform_device *pdev, struct gpio_nand *priv); + int err = 0; + + if (pdata) { + partitions = pdata->parts; + num_partitions = pdata->num_parts; + } + + /* Allocate memory for MTD device structure and private data */ + priv = devm_kzalloc(&pdev->dev, sizeof(struct gpio_nand), + GFP_KERNEL); + if (!priv) + return -ENOMEM; + + this = &priv->nand_chip; + + mtd = nand_to_mtd(this); + mtd->dev.parent = &pdev->dev; + + nand_set_controller_data(this, priv); + nand_set_flash_node(this, pdev->dev.of_node); + + priv->gpiod_rdy = devm_gpiod_get_optional(&pdev->dev, "rdy", GPIOD_IN); + if (IS_ERR(priv->gpiod_rdy)) { + err = PTR_ERR(priv->gpiod_rdy); + dev_warn(&pdev->dev, "RDY GPIO request failed (%d)\n", err); + return err; + } + + platform_set_drvdata(pdev, priv); + + /* Set chip enabled but write protected */ + priv->gpiod_nwp = devm_gpiod_get_optional(&pdev->dev, "nwp", + GPIOD_OUT_HIGH); + if (IS_ERR(priv->gpiod_nwp)) { + err = PTR_ERR(priv->gpiod_nwp); + dev_err(&pdev->dev, "NWP GPIO request failed (%d)\n", err); + return err; + } + + priv->gpiod_nce = devm_gpiod_get_optional(&pdev->dev, "nce", + GPIOD_OUT_LOW); + if (IS_ERR(priv->gpiod_nce)) { + err = PTR_ERR(priv->gpiod_nce); + dev_err(&pdev->dev, "NCE GPIO request failed (%d)\n", err); + return err; + } + + priv->gpiod_nre = devm_gpiod_get_optional(&pdev->dev, "nre", + GPIOD_OUT_LOW); + if (IS_ERR(priv->gpiod_nre)) { + err = PTR_ERR(priv->gpiod_nre); + dev_err(&pdev->dev, "NRE GPIO request failed (%d)\n", err); + return err; + } + + priv->gpiod_nwe = devm_gpiod_get_optional(&pdev->dev, "nwe", + GPIOD_OUT_LOW); + if (IS_ERR(priv->gpiod_nwe)) { + err = PTR_ERR(priv->gpiod_nwe); + dev_err(&pdev->dev, "NWE GPIO request failed (%d)\n", err); + return err; + } + + priv->gpiod_ale = devm_gpiod_get(&pdev->dev, "ale", GPIOD_OUT_LOW); + if (IS_ERR(priv->gpiod_ale)) { + err = PTR_ERR(priv->gpiod_ale); + dev_err(&pdev->dev, "ALE GPIO request failed (%d)\n", err); + return err; + } + + priv->gpiod_cle = devm_gpiod_get(&pdev->dev, "cle", GPIOD_OUT_LOW); + if (IS_ERR(priv->gpiod_cle)) { + err = PTR_ERR(priv->gpiod_cle); + dev_err(&pdev->dev, "CLE GPIO request failed (%d)\n", err); + return err; + } + + /* Request array of data pins, initialize them as input */ + priv->data_gpiods = devm_gpiod_get_array_optional(&pdev->dev, "data", + GPIOD_IN); + if (IS_ERR(priv->data_gpiods)) { + err = PTR_ERR(priv->data_gpiods); + dev_err(&pdev->dev, "data GPIO request failed: %d\n", err); + return err; + } + if (priv->data_gpiods) { + if (!priv->gpiod_nwe) { + dev_err(&pdev->dev, + "mandatory NWE pin not provided by platform\n"); + return -ENODEV; + } + + priv->io_read = gpio_nand_io_read; + priv->io_write = gpio_nand_io_write; + priv->data_in = true; + } + + if (pdev->id_entry) + probe = (void *) pdev->id_entry->driver_data; + else + probe = of_device_get_match_data(&pdev->dev); + if (probe) + err = probe(pdev, priv); + if (err) + return err; + + if (!priv->io_read || !priv->io_write) { + dev_err(&pdev->dev, "incomplete device configuration\n"); + return -ENODEV; + } + + /* Initialize the NAND controller object embedded in gpio_nand. */ + priv->base.ops = &gpio_nand_ops; + nand_controller_init(&priv->base); + this->controller = &priv->base; + + /* + * FIXME: We should release write protection only after nand_scan() to + * be on the safe side but we can't do that until we have a generic way + * to assert/deassert WP from the core. Even if the core shouldn't + * write things in the nand_scan() path, it should have control on this + * pin just in case we ever need to disable write protection during + * chip detection/initialization. + */ + /* Release write protection */ + gpiod_set_value(priv->gpiod_nwp, 0); + + /* + * This driver assumes that the default ECC engine should be TYPE_SOFT. + * Set ->engine_type before registering the NAND devices in order to + * provide a driver specific default value. + */ + this->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT; + + /* Scan to find existence of the device */ + err = nand_scan(this, 1); + if (err) + return err; + + /* Register the partitions */ + err = mtd_device_register(mtd, partitions, num_partitions); + if (err) + goto err_nand_cleanup; + + return 0; + +err_nand_cleanup: + nand_cleanup(this); + + return err; +} + +/* + * Clean up routine + */ +static int gpio_nand_remove(struct platform_device *pdev) +{ + struct gpio_nand *priv = platform_get_drvdata(pdev); + struct mtd_info *mtd = nand_to_mtd(&priv->nand_chip); + int ret; + + /* Apply write protection */ + gpiod_set_value(priv->gpiod_nwp, 1); + + /* Unregister device */ + ret = mtd_device_unregister(mtd); + WARN_ON(ret); + nand_cleanup(mtd_to_nand(mtd)); + + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id gpio_nand_of_id_table[] = { + { + /* sentinel */ + }, +}; +MODULE_DEVICE_TABLE(of, gpio_nand_of_id_table); +#endif + +static const struct platform_device_id gpio_nand_plat_id_table[] = { + { + .name = "ams-delta-nand", + }, { + /* sentinel */ + }, +}; +MODULE_DEVICE_TABLE(platform, gpio_nand_plat_id_table); + +static struct platform_driver gpio_nand_driver = { + .probe = gpio_nand_probe, + .remove = gpio_nand_remove, + .id_table = gpio_nand_plat_id_table, + .driver = { + .name = "ams-delta-nand", + .of_match_table = of_match_ptr(gpio_nand_of_id_table), + }, +}; + +module_platform_driver(gpio_nand_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Jonathan McDowell <noodles@earth.li>"); +MODULE_DESCRIPTION("Glue layer for NAND flash on Amstrad E3 (Delta)"); |