1/*
  2 *  drivers/mtd/nand/nomadik_nand.c
  3 *
  4 *  Overview:
  5 *  	Driver for on-board NAND flash on Nomadik Platforms
  6 *
  7 * Copyright © 2007 STMicroelectronics Pvt. Ltd.
  8 * Author: Sachin Verma <sachin.verma@st.com>
  9 *
 10 * Copyright © 2009 Alessandro Rubini
 11 *
 12 * This program is free software; you can redistribute it and/or modify
 13 * it under the terms of the GNU General Public License as published by
 14 * the Free Software Foundation; either version 2 of the License, or
 15 * (at your option) any later version.
 16 *
 17 * This program is distributed in the hope that it will be useful,
 18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 20 * GNU General Public License for more details.
 21 *
 22 */
 23
 24#include <linux/init.h>
 25#include <linux/module.h>
 26#include <linux/types.h>
 27#include <linux/mtd/mtd.h>
 28#include <linux/mtd/nand.h>
 29#include <linux/mtd/nand_ecc.h>
 30#include <linux/platform_device.h>
 31#include <linux/mtd/partitions.h>
 32#include <linux/io.h>
 33#include <linux/slab.h>
 34#include <mach/nand.h>
 35#include <mach/fsmc.h>
 36
 37#include <mtd/mtd-abi.h>
 38
 39struct nomadik_nand_host {
 40	struct mtd_info		mtd;
 41	struct nand_chip	nand;
 42	void __iomem *data_va;
 43	void __iomem *cmd_va;
 44	void __iomem *addr_va;
 45	struct nand_bbt_descr *bbt_desc;
 46};
 47
 48static struct nand_ecclayout nomadik_ecc_layout = {
 49	.eccbytes = 3 * 4,
 50	.eccpos = { /* each subpage has 16 bytes: pos 2,3,4 hosts ECC */
 51		0x02, 0x03, 0x04,
 52		0x12, 0x13, 0x14,
 53		0x22, 0x23, 0x24,
 54		0x32, 0x33, 0x34},
 55	/* let's keep bytes 5,6,7 for us, just in case we change ECC algo */
 56	.oobfree = { {0x08, 0x08}, {0x18, 0x08}, {0x28, 0x08}, {0x38, 0x08} },
 57};
 58
 59static void nomadik_ecc_control(struct mtd_info *mtd, int mode)
 60{
 61	/* No need to enable hw ecc, it's on by default */
 62}
 63
 64static void nomadik_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
 65{
 66	struct nand_chip *nand = mtd->priv;
 67	struct nomadik_nand_host *host = nand->priv;
 68
 69	if (cmd == NAND_CMD_NONE)
 70		return;
 71
 72	if (ctrl & NAND_CLE)
 73		writeb(cmd, host->cmd_va);
 74	else
 75		writeb(cmd, host->addr_va);
 76}
 77
 78static int nomadik_nand_probe(struct platform_device *pdev)
 79{
 80	struct nomadik_nand_platform_data *pdata = pdev->dev.platform_data;
 81	struct nomadik_nand_host *host;
 82	struct mtd_info *mtd;
 83	struct nand_chip *nand;
 84	struct resource *res;
 85	int ret = 0;
 86
 87	/* Allocate memory for the device structure (and zero it) */
 88	host = kzalloc(sizeof(struct nomadik_nand_host), GFP_KERNEL);
 89	if (!host) {
 90		dev_err(&pdev->dev, "Failed to allocate device structure.\n");
 91		return -ENOMEM;
 92	}
 93
 94	/* Call the client's init function, if any */
 95	if (pdata->init)
 96		ret = pdata->init();
 97	if (ret < 0) {
 98		dev_err(&pdev->dev, "Init function failed\n");
 99		goto err;
100	}
101
102	/* ioremap three regions */
103	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_addr");
104	if (!res) {
105		ret = -EIO;
106		goto err_unmap;
107	}
108	host->addr_va = ioremap(res->start, resource_size(res));
109
110	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_data");
111	if (!res) {
112		ret = -EIO;
113		goto err_unmap;
114	}
115	host->data_va = ioremap(res->start, resource_size(res));
116
117	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_cmd");
118	if (!res) {
119		ret = -EIO;
120		goto err_unmap;
121	}
122	host->cmd_va = ioremap(res->start, resource_size(res));
123
124	if (!host->addr_va || !host->data_va || !host->cmd_va) {
125		ret = -ENOMEM;
126		goto err_unmap;
127	}
128
129	/* Link all private pointers */
130	mtd = &host->mtd;
131	nand = &host->nand;
132	mtd->priv = nand;
133	nand->priv = host;
134
135	host->mtd.owner = THIS_MODULE;
136	nand->IO_ADDR_R = host->data_va;
137	nand->IO_ADDR_W = host->data_va;
138	nand->cmd_ctrl = nomadik_cmd_ctrl;
139
140	/*
141	 * This stanza declares ECC_HW but uses soft routines. It's because
142	 * HW claims to make the calculation but not the correction. However,
143	 * I haven't managed to get the desired data out of it until now.
144	 */
145	nand->ecc.mode = NAND_ECC_SOFT;
146	nand->ecc.layout = &nomadik_ecc_layout;
147	nand->ecc.hwctl = nomadik_ecc_control;
148	nand->ecc.size = 512;
149	nand->ecc.bytes = 3;
150
151	nand->options = pdata->options;
152
153	/*
154	 * Scan to find existence of the device
155	 */
156	if (nand_scan(&host->mtd, 1)) {
157		ret = -ENXIO;
158		goto err_unmap;
159	}
160
161	mtd_device_register(&host->mtd, pdata->parts, pdata->nparts);
162
163	platform_set_drvdata(pdev, host);
164	return 0;
165
166 err_unmap:
167	if (host->cmd_va)
168		iounmap(host->cmd_va);
169	if (host->data_va)
170		iounmap(host->data_va);
171	if (host->addr_va)
172		iounmap(host->addr_va);
173 err:
174	kfree(host);
175	return ret;
176}
177
178/*
179 * Clean up routine
180 */
181static int nomadik_nand_remove(struct platform_device *pdev)
182{
183	struct nomadik_nand_host *host = platform_get_drvdata(pdev);
184	struct nomadik_nand_platform_data *pdata = pdev->dev.platform_data;
185
186	if (pdata->exit)
187		pdata->exit();
188
189	if (host) {
190		iounmap(host->cmd_va);
191		iounmap(host->data_va);
192		iounmap(host->addr_va);
193		kfree(host);
194	}
195	return 0;
196}
197
198static int nomadik_nand_suspend(struct device *dev)
199{
200	struct nomadik_nand_host *host = dev_get_drvdata(dev);
201	int ret = 0;
202	if (host)
203		ret = host->mtd.suspend(&host->mtd);
204	return ret;
205}
206
207static int nomadik_nand_resume(struct device *dev)
208{
209	struct nomadik_nand_host *host = dev_get_drvdata(dev);
210	if (host)
211		host->mtd.resume(&host->mtd);
212	return 0;
213}
214
215static const struct dev_pm_ops nomadik_nand_pm_ops = {
216	.suspend = nomadik_nand_suspend,
217	.resume = nomadik_nand_resume,
218};
219
220static struct platform_driver nomadik_nand_driver = {
221	.probe = nomadik_nand_probe,
222	.remove = nomadik_nand_remove,
223	.driver = {
224		.owner = THIS_MODULE,
225		.name = "nomadik_nand",
226		.pm = &nomadik_nand_pm_ops,
227	},
228};
229
230static int __init nand_nomadik_init(void)
231{
232	pr_info("Nomadik NAND driver\n");
233	return platform_driver_register(&nomadik_nand_driver);
234}
235
236static void __exit nand_nomadik_exit(void)
237{
238	platform_driver_unregister(&nomadik_nand_driver);
239}
240
241module_init(nand_nomadik_init);
242module_exit(nand_nomadik_exit);
243
244MODULE_LICENSE("GPL");
245MODULE_AUTHOR("ST Microelectronics (sachin.verma@st.com)");
246MODULE_DESCRIPTION("NAND driver for Nomadik Platform");