diff options
Diffstat (limited to 'kernel/drivers/mtd/nand/cmx270_nand.c')
| -rw-r--r-- | kernel/drivers/mtd/nand/cmx270_nand.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/kernel/drivers/mtd/nand/cmx270_nand.c b/kernel/drivers/mtd/nand/cmx270_nand.c new file mode 100644 index 000000000..66ec95e6c --- /dev/null +++ b/kernel/drivers/mtd/nand/cmx270_nand.c @@ -0,0 +1,250 @@ +/* + * linux/drivers/mtd/nand/cmx270-nand.c + * + * Copyright (C) 2006 Compulab, Ltd. + * Mike Rapoport <mike@compulab.co.il> + * + * Derived from drivers/mtd/nand/h1910.c + * Copyright (C) 2002 Marius Gröger (mag@sysgo.de) + * Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de) + * + * + * 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. + * + * Overview: + * This is a device driver for the NAND flash device found on the + * CM-X270 board. + */ + +#include <linux/mtd/nand.h> +#include <linux/mtd/partitions.h> +#include <linux/slab.h> +#include <linux/gpio.h> +#include <linux/module.h> + +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/mach-types.h> + +#include <mach/pxa2xx-regs.h> + +#define GPIO_NAND_CS (11) +#define GPIO_NAND_RB (89) + +/* MTD structure for CM-X270 board */ +static struct mtd_info *cmx270_nand_mtd; + +/* remaped IO address of the device */ +static void __iomem *cmx270_nand_io; + +/* + * Define static partitions for flash device + */ +static struct mtd_partition partition_info[] = { + [0] = { + .name = "cmx270-0", + .offset = 0, + .size = MTDPART_SIZ_FULL + } +}; +#define NUM_PARTITIONS (ARRAY_SIZE(partition_info)) + +static u_char cmx270_read_byte(struct mtd_info *mtd) +{ + struct nand_chip *this = mtd->priv; + + return (readl(this->IO_ADDR_R) >> 16); +} + +static void cmx270_write_buf(struct mtd_info *mtd, const u_char *buf, int len) +{ + int i; + struct nand_chip *this = mtd->priv; + + for (i=0; i<len; i++) + writel((*buf++ << 16), this->IO_ADDR_W); +} + +static void cmx270_read_buf(struct mtd_info *mtd, u_char *buf, int len) +{ + int i; + struct nand_chip *this = mtd->priv; + + for (i=0; i<len; i++) + *buf++ = readl(this->IO_ADDR_R) >> 16; +} + +static inline void nand_cs_on(void) +{ + gpio_set_value(GPIO_NAND_CS, 0); +} + +static void nand_cs_off(void) +{ + dsb(); + + gpio_set_value(GPIO_NAND_CS, 1); +} + +/* + * hardware specific access to control-lines + */ +static void cmx270_hwcontrol(struct mtd_info *mtd, int dat, + unsigned int ctrl) +{ + struct nand_chip* this = mtd->priv; + unsigned int nandaddr = (unsigned int)this->IO_ADDR_W; + + dsb(); + + if (ctrl & NAND_CTRL_CHANGE) { + if ( ctrl & NAND_ALE ) + nandaddr |= (1 << 3); + else + nandaddr &= ~(1 << 3); + if ( ctrl & NAND_CLE ) + nandaddr |= (1 << 2); + else + nandaddr &= ~(1 << 2); + if ( ctrl & NAND_NCE ) + nand_cs_on(); + else + nand_cs_off(); + } + + dsb(); + this->IO_ADDR_W = (void __iomem*)nandaddr; + if (dat != NAND_CMD_NONE) + writel((dat << 16), this->IO_ADDR_W); + + dsb(); +} + +/* + * read device ready pin + */ +static int cmx270_device_ready(struct mtd_info *mtd) +{ + dsb(); + + return (gpio_get_value(GPIO_NAND_RB)); +} + +/* + * Main initialization routine + */ +static int __init cmx270_init(void) +{ + struct nand_chip *this; + int ret; + + if (!(machine_is_armcore() && cpu_is_pxa27x())) + return -ENODEV; + + ret = gpio_request(GPIO_NAND_CS, "NAND CS"); + if (ret) { + pr_warning("CM-X270: failed to request NAND CS gpio\n"); + return ret; + } + + gpio_direction_output(GPIO_NAND_CS, 1); + + ret = gpio_request(GPIO_NAND_RB, "NAND R/B"); + if (ret) { + pr_warning("CM-X270: failed to request NAND R/B gpio\n"); + goto err_gpio_request; + } + + gpio_direction_input(GPIO_NAND_RB); + + /* Allocate memory for MTD device structure and private data */ + cmx270_nand_mtd = kzalloc(sizeof(struct mtd_info) + + sizeof(struct nand_chip), + GFP_KERNEL); + if (!cmx270_nand_mtd) { + ret = -ENOMEM; + goto err_kzalloc; + } + + cmx270_nand_io = ioremap(PXA_CS1_PHYS, 12); + if (!cmx270_nand_io) { + pr_debug("Unable to ioremap NAND device\n"); + ret = -EINVAL; + goto err_ioremap; + } + + /* Get pointer to private data */ + this = (struct nand_chip *)(&cmx270_nand_mtd[1]); + + /* Link the private data with the MTD structure */ + cmx270_nand_mtd->owner = THIS_MODULE; + cmx270_nand_mtd->priv = this; + + /* insert callbacks */ + this->IO_ADDR_R = cmx270_nand_io; + this->IO_ADDR_W = cmx270_nand_io; + this->cmd_ctrl = cmx270_hwcontrol; + this->dev_ready = cmx270_device_ready; + + /* 15 us command delay time */ + this->chip_delay = 20; + this->ecc.mode = NAND_ECC_SOFT; + + /* read/write functions */ + this->read_byte = cmx270_read_byte; + this->read_buf = cmx270_read_buf; + this->write_buf = cmx270_write_buf; + + /* Scan to find existence of the device */ + if (nand_scan (cmx270_nand_mtd, 1)) { + pr_notice("No NAND device\n"); + ret = -ENXIO; + goto err_scan; + } + + /* Register the partitions */ + ret = mtd_device_parse_register(cmx270_nand_mtd, NULL, NULL, + partition_info, NUM_PARTITIONS); + if (ret) + goto err_scan; + + /* Return happy */ + return 0; + +err_scan: + iounmap(cmx270_nand_io); +err_ioremap: + kfree(cmx270_nand_mtd); +err_kzalloc: + gpio_free(GPIO_NAND_RB); +err_gpio_request: + gpio_free(GPIO_NAND_CS); + + return ret; + +} +module_init(cmx270_init); + +/* + * Clean up routine + */ +static void __exit cmx270_cleanup(void) +{ + /* Release resources, unregister device */ + nand_release(cmx270_nand_mtd); + + gpio_free(GPIO_NAND_RB); + gpio_free(GPIO_NAND_CS); + + iounmap(cmx270_nand_io); + + /* Free the MTD device structure */ + kfree (cmx270_nand_mtd); +} +module_exit(cmx270_cleanup); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>"); +MODULE_DESCRIPTION("NAND flash driver for Compulab CM-X270 Module"); |