Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /* drivers/mtd/maps/plat-ram.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  * (c) 2004-2005 Simtec Electronics
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  *	http://www.simtec.co.uk/products/SWLINUX/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  *	Ben Dooks <ben@simtec.co.uk>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  * Generic platform device based RAM map
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/string.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include <linux/ioport.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include <linux/device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #include <linux/mtd/mtd.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) #include <linux/mtd/map.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) #include <linux/mtd/partitions.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) #include <linux/mtd/plat-ram.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) #include <asm/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) /* private structure for each mtd platform ram device created */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) struct platram_info {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 	struct device		*dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 	struct mtd_info		*mtd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 	struct map_info		 map;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	struct platdata_mtd_ram	*pdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) /* to_platram_info()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38)  * device private data to struct platram_info conversion
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) static inline struct platram_info *to_platram_info(struct platform_device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	return platform_get_drvdata(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) /* platram_setrw
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48)  * call the platform device's set rw/ro control
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50)  * to = 0 => read-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51)  *    = 1 => read-write
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) static inline void platram_setrw(struct platram_info *info, int to)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 	if (info->pdata == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	if (info->pdata->set_rw != NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 		(info->pdata->set_rw)(info->dev, to);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) /* platram_remove
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65)  * called to remove the device from the driver's control
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) static int platram_remove(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	struct platram_info *info = to_platram_info(pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	dev_dbg(&pdev->dev, "removing device\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 	if (info == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	if (info->mtd) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 		mtd_device_unregister(info->mtd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 		map_destroy(info->mtd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 	/* ensure ram is left read-only */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 	platram_setrw(info, PLATRAM_RO);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 	kfree(info);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) /* platram_probe
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93)  * called from device drive system when a device matching our
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94)  * driver is found.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) static int platram_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	struct platdata_mtd_ram	*pdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 	struct platram_info *info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 	struct resource *res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	int err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 	dev_dbg(&pdev->dev, "probe entered\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	if (dev_get_platdata(&pdev->dev) == NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 		dev_err(&pdev->dev, "no platform data supplied\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 		err = -ENOENT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 		goto exit_error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	pdata = dev_get_platdata(&pdev->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 	info = kzalloc(sizeof(*info), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 	if (info == NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 		err = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 		goto exit_error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 	platform_set_drvdata(pdev, info);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	info->dev = &pdev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 	info->pdata = pdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 	/* get the resource for the memory mapping */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	info->map.virt = devm_ioremap_resource(&pdev->dev, res);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 	if (IS_ERR(info->map.virt)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 		err = PTR_ERR(info->map.virt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 		dev_err(&pdev->dev, "failed to ioremap() region\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 		goto exit_free;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	dev_dbg(&pdev->dev, "got platform resource %p (0x%llx)\n", res,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 		(unsigned long long)res->start);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 	/* setup map parameters */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 	info->map.phys = res->start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 	info->map.size = resource_size(res);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 	info->map.name = pdata->mapname != NULL ?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 			(char *)pdata->mapname : (char *)pdev->name;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 	info->map.bankwidth = pdata->bankwidth;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 	dev_dbg(&pdev->dev, "virt %p, %lu bytes\n", info->map.virt, info->map.size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 	simple_map_init(&info->map);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	dev_dbg(&pdev->dev, "initialised map, probing for mtd\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	/* probe for the right mtd map driver
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	 * supplied by the platform_data struct */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	if (pdata->map_probes) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 		const char * const *map_probes = pdata->map_probes;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 		for ( ; !info->mtd && *map_probes; map_probes++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 			info->mtd = do_map_probe(*map_probes , &info->map);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	/* fallback to map_ram */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 		info->mtd = do_map_probe("map_ram", &info->map);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 	if (info->mtd == NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 		dev_err(&pdev->dev, "failed to probe for map_ram\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 		err = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 		goto exit_free;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 	info->mtd->dev.parent = &pdev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 	platram_setrw(info, PLATRAM_RW);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 	/* check to see if there are any available partitions, or whether
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 	 * to add this device whole */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	err = mtd_device_parse_register(info->mtd, pdata->probes, NULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 					pdata->partitions,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 					pdata->nr_partitions);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 	if (!err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 		dev_info(&pdev->dev, "registered mtd device\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	if (pdata->nr_partitions) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 		/* add the whole device. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 		err = mtd_device_register(info->mtd, NULL, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 		if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 			dev_err(&pdev->dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 				"failed to register the entire device\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194)  exit_free:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 	platram_remove(pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196)  exit_error:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 	return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) /* device driver info */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) /* work with hotplug and coldplug */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) MODULE_ALIAS("platform:mtd-ram");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) static struct platform_driver platram_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 	.probe		= platram_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 	.remove		= platram_remove,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) 	.driver		= {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 		.name	= "mtd-ram",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) 	},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) module_platform_driver(platram_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) MODULE_DESCRIPTION("MTD platform RAM map driver");