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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Copyright (C) 2006 Compulab, Ltd.
4  *  Mike Rapoport <mike@compulab.co.il>
5  *
6  *  Derived from drivers/mtd/nand/h1910.c (removed in v3.10)
7  *       Copyright (C) 2002 Marius Gröger (mag@sysgo.de)
8  *       Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
9  *
10  *  Overview:
11  *   This is a device driver for the NAND flash device found on the
12  *   CM-X270 board.
13  */
14 
15 #include <linux/mtd/rawnand.h>
16 #include <linux/mtd/partitions.h>
17 #include <linux/slab.h>
18 #include <linux/gpio.h>
19 #include <linux/module.h>
20 
21 #include <asm/io.h>
22 #include <asm/irq.h>
23 #include <asm/mach-types.h>
24 
25 #include <mach/pxa2xx-regs.h>
26 
27 #define GPIO_NAND_CS	(11)
28 #define GPIO_NAND_RB	(89)
29 
30 /* MTD structure for CM-X270 board */
31 static struct mtd_info *cmx270_nand_mtd;
32 
33 /* remaped IO address of the device */
34 static void __iomem *cmx270_nand_io;
35 
36 /*
37  * Define static partitions for flash device
38  */
39 static const struct mtd_partition partition_info[] = {
40 	[0] = {
41 		.name	= "cmx270-0",
42 		.offset	= 0,
43 		.size	= MTDPART_SIZ_FULL
44 	}
45 };
46 #define NUM_PARTITIONS (ARRAY_SIZE(partition_info))
47 
cmx270_read_byte(struct nand_chip * this)48 static u_char cmx270_read_byte(struct nand_chip *this)
49 {
50 	return (readl(this->legacy.IO_ADDR_R) >> 16);
51 }
52 
cmx270_write_buf(struct nand_chip * this,const u_char * buf,int len)53 static void cmx270_write_buf(struct nand_chip *this, const u_char *buf,
54 			     int len)
55 {
56 	int i;
57 
58 	for (i=0; i<len; i++)
59 		writel((*buf++ << 16), this->legacy.IO_ADDR_W);
60 }
61 
cmx270_read_buf(struct nand_chip * this,u_char * buf,int len)62 static void cmx270_read_buf(struct nand_chip *this, u_char *buf, int len)
63 {
64 	int i;
65 
66 	for (i=0; i<len; i++)
67 		*buf++ = readl(this->legacy.IO_ADDR_R) >> 16;
68 }
69 
nand_cs_on(void)70 static inline void nand_cs_on(void)
71 {
72 	gpio_set_value(GPIO_NAND_CS, 0);
73 }
74 
nand_cs_off(void)75 static void nand_cs_off(void)
76 {
77 	dsb();
78 
79 	gpio_set_value(GPIO_NAND_CS, 1);
80 }
81 
82 /*
83  *	hardware specific access to control-lines
84  */
cmx270_hwcontrol(struct nand_chip * this,int dat,unsigned int ctrl)85 static void cmx270_hwcontrol(struct nand_chip *this, int dat,
86 			     unsigned int ctrl)
87 {
88 	unsigned int nandaddr = (unsigned int)this->legacy.IO_ADDR_W;
89 
90 	dsb();
91 
92 	if (ctrl & NAND_CTRL_CHANGE) {
93 		if ( ctrl & NAND_ALE )
94 			nandaddr |=  (1 << 3);
95 		else
96 			nandaddr &= ~(1 << 3);
97 		if ( ctrl & NAND_CLE )
98 			nandaddr |=  (1 << 2);
99 		else
100 			nandaddr &= ~(1 << 2);
101 		if ( ctrl & NAND_NCE )
102 			nand_cs_on();
103 		else
104 			nand_cs_off();
105 	}
106 
107 	dsb();
108 	this->legacy.IO_ADDR_W = (void __iomem*)nandaddr;
109 	if (dat != NAND_CMD_NONE)
110 		writel((dat << 16), this->legacy.IO_ADDR_W);
111 
112 	dsb();
113 }
114 
115 /*
116  *	read device ready pin
117  */
cmx270_device_ready(struct nand_chip * this)118 static int cmx270_device_ready(struct nand_chip *this)
119 {
120 	dsb();
121 
122 	return (gpio_get_value(GPIO_NAND_RB));
123 }
124 
125 /*
126  * Main initialization routine
127  */
cmx270_init(void)128 static int __init cmx270_init(void)
129 {
130 	struct nand_chip *this;
131 	int ret;
132 
133 	if (!(machine_is_armcore() && cpu_is_pxa27x()))
134 		return -ENODEV;
135 
136 	ret = gpio_request(GPIO_NAND_CS, "NAND CS");
137 	if (ret) {
138 		pr_warn("CM-X270: failed to request NAND CS gpio\n");
139 		return ret;
140 	}
141 
142 	gpio_direction_output(GPIO_NAND_CS, 1);
143 
144 	ret = gpio_request(GPIO_NAND_RB, "NAND R/B");
145 	if (ret) {
146 		pr_warn("CM-X270: failed to request NAND R/B gpio\n");
147 		goto err_gpio_request;
148 	}
149 
150 	gpio_direction_input(GPIO_NAND_RB);
151 
152 	/* Allocate memory for MTD device structure and private data */
153 	this = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
154 	if (!this) {
155 		ret = -ENOMEM;
156 		goto err_kzalloc;
157 	}
158 
159 	cmx270_nand_io = ioremap(PXA_CS1_PHYS, 12);
160 	if (!cmx270_nand_io) {
161 		pr_debug("Unable to ioremap NAND device\n");
162 		ret = -EINVAL;
163 		goto err_ioremap;
164 	}
165 
166 	cmx270_nand_mtd = nand_to_mtd(this);
167 
168 	/* Link the private data with the MTD structure */
169 	cmx270_nand_mtd->owner = THIS_MODULE;
170 
171 	/* insert callbacks */
172 	this->legacy.IO_ADDR_R = cmx270_nand_io;
173 	this->legacy.IO_ADDR_W = cmx270_nand_io;
174 	this->legacy.cmd_ctrl = cmx270_hwcontrol;
175 	this->legacy.dev_ready = cmx270_device_ready;
176 
177 	/* 15 us command delay time */
178 	this->legacy.chip_delay = 20;
179 	this->ecc.mode = NAND_ECC_SOFT;
180 	this->ecc.algo = NAND_ECC_HAMMING;
181 
182 	/* read/write functions */
183 	this->legacy.read_byte = cmx270_read_byte;
184 	this->legacy.read_buf = cmx270_read_buf;
185 	this->legacy.write_buf = cmx270_write_buf;
186 
187 	/* Scan to find existence of the device */
188 	ret = nand_scan(this, 1);
189 	if (ret) {
190 		pr_notice("No NAND device\n");
191 		goto err_scan;
192 	}
193 
194 	/* Register the partitions */
195 	ret = mtd_device_register(cmx270_nand_mtd, partition_info,
196 				  NUM_PARTITIONS);
197 	if (ret)
198 		goto err_scan;
199 
200 	/* Return happy */
201 	return 0;
202 
203 err_scan:
204 	iounmap(cmx270_nand_io);
205 err_ioremap:
206 	kfree(this);
207 err_kzalloc:
208 	gpio_free(GPIO_NAND_RB);
209 err_gpio_request:
210 	gpio_free(GPIO_NAND_CS);
211 
212 	return ret;
213 
214 }
215 module_init(cmx270_init);
216 
217 /*
218  * Clean up routine
219  */
cmx270_cleanup(void)220 static void __exit cmx270_cleanup(void)
221 {
222 	/* Release resources, unregister device */
223 	nand_release(mtd_to_nand(cmx270_nand_mtd));
224 
225 	gpio_free(GPIO_NAND_RB);
226 	gpio_free(GPIO_NAND_CS);
227 
228 	iounmap(cmx270_nand_io);
229 
230 	kfree(mtd_to_nand(cmx270_nand_mtd));
231 }
232 module_exit(cmx270_cleanup);
233 
234 MODULE_LICENSE("GPL");
235 MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
236 MODULE_DESCRIPTION("NAND flash driver for Compulab CM-X270 Module");
237