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author | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
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committer | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
commit | 871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch) | |
tree | 8718f573808810c2a1e8cb8fb6ac469093ca2784 /drivers/mtd/nand/gpio.c | |
parent | 9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff) | |
download | FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.gz FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.bz2 FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.zip |
Moved, renamed, and deleted files
The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.
Diffstat (limited to 'drivers/mtd/nand/gpio.c')
-rw-r--r-- | drivers/mtd/nand/gpio.c | 476 |
1 files changed, 476 insertions, 0 deletions
diff --git a/drivers/mtd/nand/gpio.c b/drivers/mtd/nand/gpio.c new file mode 100644 index 00000000..27000a5f --- /dev/null +++ b/drivers/mtd/nand/gpio.c @@ -0,0 +1,476 @@ +/* + * drivers/mtd/nand/gpio.c + * + * Updated, and converted to generic GPIO based driver by Russell King. + * + * Written by Ben Dooks <ben@simtec.co.uk> + * Based on 2.4 version by Mark Whittaker + * + * © 2004 Simtec Electronics + * + * Device driver for NAND connected via GPIO + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/gpio.h> +#include <linux/io.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/nand.h> +#include <linux/mtd/partitions.h> +#include <linux/mtd/nand-gpio.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_gpio.h> + +struct gpiomtd { + void __iomem *io_sync; + struct mtd_info mtd_info; + struct nand_chip nand_chip; + struct gpio_nand_platdata plat; +}; + +#define gpio_nand_getpriv(x) container_of(x, struct gpiomtd, mtd_info) + + +#ifdef CONFIG_ARM +/* gpio_nand_dosync() + * + * Make sure the GPIO state changes occur in-order with writes to NAND + * memory region. + * Needed on PXA due to bus-reordering within the SoC itself (see section on + * I/O ordering in PXA manual (section 2.3, p35) + */ +static void gpio_nand_dosync(struct gpiomtd *gpiomtd) +{ + unsigned long tmp; + + if (gpiomtd->io_sync) { + /* + * Linux memory barriers don't cater for what's required here. + * What's required is what's here - a read from a separate + * region with a dependency on that read. + */ + tmp = readl(gpiomtd->io_sync); + asm volatile("mov %1, %0\n" : "=r" (tmp) : "r" (tmp)); + } +} +#else +static inline void gpio_nand_dosync(struct gpiomtd *gpiomtd) {} +#endif + +static void gpio_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl) +{ + struct gpiomtd *gpiomtd = gpio_nand_getpriv(mtd); + + gpio_nand_dosync(gpiomtd); + + if (ctrl & NAND_CTRL_CHANGE) { + gpio_set_value(gpiomtd->plat.gpio_nce, !(ctrl & NAND_NCE)); + gpio_set_value(gpiomtd->plat.gpio_cle, !!(ctrl & NAND_CLE)); + gpio_set_value(gpiomtd->plat.gpio_ale, !!(ctrl & NAND_ALE)); + gpio_nand_dosync(gpiomtd); + } + if (cmd == NAND_CMD_NONE) + return; + + writeb(cmd, gpiomtd->nand_chip.IO_ADDR_W); + gpio_nand_dosync(gpiomtd); +} + +static void gpio_nand_writebuf(struct mtd_info *mtd, const u_char *buf, int len) +{ + struct nand_chip *this = mtd->priv; + + writesb(this->IO_ADDR_W, buf, len); +} + +static void gpio_nand_readbuf(struct mtd_info *mtd, u_char *buf, int len) +{ + struct nand_chip *this = mtd->priv; + + readsb(this->IO_ADDR_R, buf, len); +} + +static int gpio_nand_verifybuf(struct mtd_info *mtd, const u_char *buf, int len) +{ + struct nand_chip *this = mtd->priv; + unsigned char read, *p = (unsigned char *) buf; + int i, err = 0; + + for (i = 0; i < len; i++) { + read = readb(this->IO_ADDR_R); + if (read != p[i]) { + pr_debug("%s: err at %d (read %04x vs %04x)\n", + __func__, i, read, p[i]); + err = -EFAULT; + } + } + return err; +} + +static void gpio_nand_writebuf16(struct mtd_info *mtd, const u_char *buf, + int len) +{ + struct nand_chip *this = mtd->priv; + + if (IS_ALIGNED((unsigned long)buf, 2)) { + writesw(this->IO_ADDR_W, buf, len>>1); + } else { + int i; + unsigned short *ptr = (unsigned short *)buf; + + for (i = 0; i < len; i += 2, ptr++) + writew(*ptr, this->IO_ADDR_W); + } +} + +static void gpio_nand_readbuf16(struct mtd_info *mtd, u_char *buf, int len) +{ + struct nand_chip *this = mtd->priv; + + if (IS_ALIGNED((unsigned long)buf, 2)) { + readsw(this->IO_ADDR_R, buf, len>>1); + } else { + int i; + unsigned short *ptr = (unsigned short *)buf; + + for (i = 0; i < len; i += 2, ptr++) + *ptr = readw(this->IO_ADDR_R); + } +} + +static int gpio_nand_verifybuf16(struct mtd_info *mtd, const u_char *buf, + int len) +{ + struct nand_chip *this = mtd->priv; + unsigned short read, *p = (unsigned short *) buf; + int i, err = 0; + len >>= 1; + + for (i = 0; i < len; i++) { + read = readw(this->IO_ADDR_R); + if (read != p[i]) { + pr_debug("%s: err at %d (read %04x vs %04x)\n", + __func__, i, read, p[i]); + err = -EFAULT; + } + } + return err; +} + + +static int gpio_nand_devready(struct mtd_info *mtd) +{ + struct gpiomtd *gpiomtd = gpio_nand_getpriv(mtd); + return gpio_get_value(gpiomtd->plat.gpio_rdy); +} + +#ifdef CONFIG_OF +static const struct of_device_id gpio_nand_id_table[] = { + { .compatible = "gpio-control-nand" }, + {} +}; +MODULE_DEVICE_TABLE(of, gpio_nand_id_table); + +static int gpio_nand_get_config_of(const struct device *dev, + struct gpio_nand_platdata *plat) +{ + u32 val; + + if (!of_property_read_u32(dev->of_node, "bank-width", &val)) { + if (val == 2) { + plat->options |= NAND_BUSWIDTH_16; + } else if (val != 1) { + dev_err(dev, "invalid bank-width %u\n", val); + return -EINVAL; + } + } + + plat->gpio_rdy = of_get_gpio(dev->of_node, 0); + plat->gpio_nce = of_get_gpio(dev->of_node, 1); + plat->gpio_ale = of_get_gpio(dev->of_node, 2); + plat->gpio_cle = of_get_gpio(dev->of_node, 3); + plat->gpio_nwp = of_get_gpio(dev->of_node, 4); + + if (!of_property_read_u32(dev->of_node, "chip-delay", &val)) + plat->chip_delay = val; + + return 0; +} + +static struct resource *gpio_nand_get_io_sync_of(struct platform_device *pdev) +{ + struct resource *r = devm_kzalloc(&pdev->dev, sizeof(*r), GFP_KERNEL); + u64 addr; + + if (!r || of_property_read_u64(pdev->dev.of_node, + "gpio-control-nand,io-sync-reg", &addr)) + return NULL; + + r->start = addr; + r->end = r->start + 0x3; + r->flags = IORESOURCE_MEM; + + return r; +} +#else /* CONFIG_OF */ +#define gpio_nand_id_table NULL +static inline int gpio_nand_get_config_of(const struct device *dev, + struct gpio_nand_platdata *plat) +{ + return -ENOSYS; +} + +static inline struct resource * +gpio_nand_get_io_sync_of(struct platform_device *pdev) +{ + return NULL; +} +#endif /* CONFIG_OF */ + +static inline int gpio_nand_get_config(const struct device *dev, + struct gpio_nand_platdata *plat) +{ + int ret = gpio_nand_get_config_of(dev, plat); + + if (!ret) + return ret; + + if (dev->platform_data) { + memcpy(plat, dev->platform_data, sizeof(*plat)); + return 0; + } + + return -EINVAL; +} + +static inline struct resource * +gpio_nand_get_io_sync(struct platform_device *pdev) +{ + struct resource *r = gpio_nand_get_io_sync_of(pdev); + + if (r) + return r; + + return platform_get_resource(pdev, IORESOURCE_MEM, 1); +} + +static int __devexit gpio_nand_remove(struct platform_device *dev) +{ + struct gpiomtd *gpiomtd = platform_get_drvdata(dev); + struct resource *res; + + nand_release(&gpiomtd->mtd_info); + + res = gpio_nand_get_io_sync(dev); + iounmap(gpiomtd->io_sync); + if (res) + release_mem_region(res->start, resource_size(res)); + + res = platform_get_resource(dev, IORESOURCE_MEM, 0); + iounmap(gpiomtd->nand_chip.IO_ADDR_R); + release_mem_region(res->start, resource_size(res)); + + if (gpio_is_valid(gpiomtd->plat.gpio_nwp)) + gpio_set_value(gpiomtd->plat.gpio_nwp, 0); + gpio_set_value(gpiomtd->plat.gpio_nce, 1); + + gpio_free(gpiomtd->plat.gpio_cle); + gpio_free(gpiomtd->plat.gpio_ale); + gpio_free(gpiomtd->plat.gpio_nce); + if (gpio_is_valid(gpiomtd->plat.gpio_nwp)) + gpio_free(gpiomtd->plat.gpio_nwp); + gpio_free(gpiomtd->plat.gpio_rdy); + + kfree(gpiomtd); + + return 0; +} + +static void __iomem *request_and_remap(struct resource *res, size_t size, + const char *name, int *err) +{ + void __iomem *ptr; + + if (!request_mem_region(res->start, resource_size(res), name)) { + *err = -EBUSY; + return NULL; + } + + ptr = ioremap(res->start, size); + if (!ptr) { + release_mem_region(res->start, resource_size(res)); + *err = -ENOMEM; + } + return ptr; +} + +static int __devinit gpio_nand_probe(struct platform_device *dev) +{ + struct gpiomtd *gpiomtd; + struct nand_chip *this; + struct resource *res0, *res1; + struct mtd_part_parser_data ppdata = {}; + int ret = 0; + + if (!dev->dev.of_node && !dev->dev.platform_data) + return -EINVAL; + + res0 = platform_get_resource(dev, IORESOURCE_MEM, 0); + if (!res0) + return -EINVAL; + + gpiomtd = kzalloc(sizeof(*gpiomtd), GFP_KERNEL); + if (gpiomtd == NULL) { + dev_err(&dev->dev, "failed to create NAND MTD\n"); + return -ENOMEM; + } + + this = &gpiomtd->nand_chip; + this->IO_ADDR_R = request_and_remap(res0, 2, "NAND", &ret); + if (!this->IO_ADDR_R) { + dev_err(&dev->dev, "unable to map NAND\n"); + goto err_map; + } + + res1 = gpio_nand_get_io_sync(dev); + if (res1) { + gpiomtd->io_sync = request_and_remap(res1, 4, "NAND sync", &ret); + if (!gpiomtd->io_sync) { + dev_err(&dev->dev, "unable to map sync NAND\n"); + goto err_sync; + } + } + + ret = gpio_nand_get_config(&dev->dev, &gpiomtd->plat); + if (ret) + goto err_nce; + + ret = gpio_request(gpiomtd->plat.gpio_nce, "NAND NCE"); + if (ret) + goto err_nce; + gpio_direction_output(gpiomtd->plat.gpio_nce, 1); + if (gpio_is_valid(gpiomtd->plat.gpio_nwp)) { + ret = gpio_request(gpiomtd->plat.gpio_nwp, "NAND NWP"); + if (ret) + goto err_nwp; + gpio_direction_output(gpiomtd->plat.gpio_nwp, 1); + } + ret = gpio_request(gpiomtd->plat.gpio_ale, "NAND ALE"); + if (ret) + goto err_ale; + gpio_direction_output(gpiomtd->plat.gpio_ale, 0); + ret = gpio_request(gpiomtd->plat.gpio_cle, "NAND CLE"); + if (ret) + goto err_cle; + gpio_direction_output(gpiomtd->plat.gpio_cle, 0); + ret = gpio_request(gpiomtd->plat.gpio_rdy, "NAND RDY"); + if (ret) + goto err_rdy; + gpio_direction_input(gpiomtd->plat.gpio_rdy); + + + this->IO_ADDR_W = this->IO_ADDR_R; + this->ecc.mode = NAND_ECC_SOFT; + this->options = gpiomtd->plat.options; + this->chip_delay = gpiomtd->plat.chip_delay; + + /* install our routines */ + this->cmd_ctrl = gpio_nand_cmd_ctrl; + this->dev_ready = gpio_nand_devready; + + if (this->options & NAND_BUSWIDTH_16) { + this->read_buf = gpio_nand_readbuf16; + this->write_buf = gpio_nand_writebuf16; + this->verify_buf = gpio_nand_verifybuf16; + } else { + this->read_buf = gpio_nand_readbuf; + this->write_buf = gpio_nand_writebuf; + this->verify_buf = gpio_nand_verifybuf; + } + + /* set the mtd private data for the nand driver */ + gpiomtd->mtd_info.priv = this; + gpiomtd->mtd_info.owner = THIS_MODULE; + + if (nand_scan(&gpiomtd->mtd_info, 1)) { + dev_err(&dev->dev, "no nand chips found?\n"); + ret = -ENXIO; + goto err_wp; + } + + if (gpiomtd->plat.adjust_parts) + gpiomtd->plat.adjust_parts(&gpiomtd->plat, + gpiomtd->mtd_info.size); + + ppdata.of_node = dev->dev.of_node; + ret = mtd_device_parse_register(&gpiomtd->mtd_info, NULL, &ppdata, + gpiomtd->plat.parts, + gpiomtd->plat.num_parts); + if (ret) + goto err_wp; + platform_set_drvdata(dev, gpiomtd); + + return 0; + +err_wp: + if (gpio_is_valid(gpiomtd->plat.gpio_nwp)) + gpio_set_value(gpiomtd->plat.gpio_nwp, 0); + gpio_free(gpiomtd->plat.gpio_rdy); +err_rdy: + gpio_free(gpiomtd->plat.gpio_cle); +err_cle: + gpio_free(gpiomtd->plat.gpio_ale); +err_ale: + if (gpio_is_valid(gpiomtd->plat.gpio_nwp)) + gpio_free(gpiomtd->plat.gpio_nwp); +err_nwp: + gpio_free(gpiomtd->plat.gpio_nce); +err_nce: + iounmap(gpiomtd->io_sync); + if (res1) + release_mem_region(res1->start, resource_size(res1)); +err_sync: + iounmap(gpiomtd->nand_chip.IO_ADDR_R); + release_mem_region(res0->start, resource_size(res0)); +err_map: + kfree(gpiomtd); + return ret; +} + +static struct platform_driver gpio_nand_driver = { + .probe = gpio_nand_probe, + .remove = gpio_nand_remove, + .driver = { + .name = "gpio-nand", + .of_match_table = gpio_nand_id_table, + }, +}; + +static int __init gpio_nand_init(void) +{ + printk(KERN_INFO "GPIO NAND driver, © 2004 Simtec Electronics\n"); + + return platform_driver_register(&gpio_nand_driver); +} + +static void __exit gpio_nand_exit(void) +{ + platform_driver_unregister(&gpio_nand_driver); +} + +module_init(gpio_nand_init); +module_exit(gpio_nand_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); +MODULE_DESCRIPTION("GPIO NAND Driver"); |