1 files changed, 287 insertions, 0 deletions
diff --git a/drivers/mtd/maps/pismo.c b/drivers/mtd/maps/pismo.c
new file mode 100644
index 000000000..946ba80f9
--- /dev/null
+++ b/drivers/mtd/maps/pismo.c
@@ -0,0 +1,287 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PISMO memory driver - http://www.pismoworld.org/
+ *
+ * For ARM Realview and Versatile platforms
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/mtd/physmap.h>
+#include <linux/mtd/plat-ram.h>
+#include <linux/mtd/pismo.h>
+
+#define PISMO_NUM_CS	5
+
+struct pismo_cs_block {
+	u8	type;
+	u8	width;
+	__le16	access;
+	__le32	size;
+	u32	reserved[2];
+	char	device[32];
+} __packed;
+
+struct pismo_eeprom {
+	struct pismo_cs_block cs[PISMO_NUM_CS];
+	char	board[15];
+	u8	sum;
+} __packed;
+
+struct pismo_mem {
+	phys_addr_t base;
+	u32	size;
+	u16	access;
+	u8	width;
+	u8	type;
+};
+
+struct pismo_data {
+	struct i2c_client	*client;
+	void			(*vpp)(void *, int);
+	void			*vpp_data;
+	struct platform_device	*dev[PISMO_NUM_CS];
+};
+
+static void pismo_set_vpp(struct platform_device *pdev, int on)
+{
+	struct i2c_client *client = to_i2c_client(pdev->dev.parent);
+	struct pismo_data *pismo = i2c_get_clientdata(client);
+
+	pismo->vpp(pismo->vpp_data, on);
+}
+
+static unsigned int pismo_width_to_bytes(unsigned int width)
+{
+	width &= 15;
+	if (width > 2)
+		return 0;
+	return 1 << width;
+}
+
+static int pismo_eeprom_read(struct i2c_client *client, void *buf, u8 addr,
+			     size_t size)
+{
+	int ret;
+	struct i2c_msg msg[] = {
+		{
+			.addr = client->addr,
+			.len = sizeof(addr),
+			.buf = &addr,
+		}, {
+			.addr = client->addr,
+			.flags = I2C_M_RD,
+			.len = size,
+			.buf = buf,
+		},
+	};
+
+	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+
+	return ret == ARRAY_SIZE(msg) ? size : -EIO;
+}
+
+static int pismo_add_device(struct pismo_data *pismo, int i,
+			    struct pismo_mem *region, const char *name,
+			    void *pdata, size_t psize)
+{
+	struct platform_device *dev;
+	struct resource res = { };
+	phys_addr_t base = region->base;
+	int ret;
+
+	if (base == ~0)
+		return -ENXIO;
+
+	res.start = base;
+	res.end = base + region->size - 1;
+	res.flags = IORESOURCE_MEM;
+
+	dev = platform_device_alloc(name, i);
+	if (!dev)
+		return -ENOMEM;
+	dev->dev.parent = &pismo->client->dev;
+
+	do {
+		ret = platform_device_add_resources(dev, &res, 1);
+		if (ret)
+			break;
+
+		ret = platform_device_add_data(dev, pdata, psize);
+		if (ret)
+			break;
+
+		ret = platform_device_add(dev);
+		if (ret)
+			break;
+
+		pismo->dev[i] = dev;
+		return 0;
+	} while (0);
+
+	platform_device_put(dev);
+	return ret;
+}
+
+static int pismo_add_nor(struct pismo_data *pismo, int i,
+			 struct pismo_mem *region)
+{
+	struct physmap_flash_data data = {
+		.width = region->width,
+	};
+
+	if (pismo->vpp)
+		data.set_vpp = pismo_set_vpp;
+
+	return pismo_add_device(pismo, i, region, "physmap-flash",
+		&data, sizeof(data));
+}
+
+static int pismo_add_sram(struct pismo_data *pismo, int i,
+			  struct pismo_mem *region)
+{
+	struct platdata_mtd_ram data = {
+		.bankwidth = region->width,
+	};
+
+	return pismo_add_device(pismo, i, region, "mtd-ram",
+		&data, sizeof(data));
+}
+
+static void pismo_add_one(struct pismo_data *pismo, int i,
+			  const struct pismo_cs_block *cs, phys_addr_t base)
+{
+	struct device *dev = &pismo->client->dev;
+	struct pismo_mem region;
+
+	region.base = base;
+	region.type = cs->type;
+	region.width = pismo_width_to_bytes(cs->width);
+	region.access = le16_to_cpu(cs->access);
+	region.size = le32_to_cpu(cs->size);
+
+	if (region.width == 0) {
+		dev_err(dev, "cs%u: bad width: %02x, ignoring\n", i, cs->width);
+		return;
+	}
+
+	/*
+	 * FIXME: may need to the platforms memory controller here, but at
+	 * the moment we assume that it has already been correctly setup.
+	 * The memory controller can also tell us the base address as well.
+	 */
+
+	dev_info(dev, "cs%u: %.32s: type %02x access %u00ps size %uK\n",
+		i, cs->device, region.type, region.access, region.size / 1024);
+
+	switch (region.type) {
+	case 0:
+		break;
+	case 1:
+		/* static DOC */
+		break;
+	case 2:
+		/* static NOR */
+		pismo_add_nor(pismo, i, &region);
+		break;
+	case 3:
+		/* static RAM */
+		pismo_add_sram(pismo, i, &region);
+		break;
+	}
+}
+
+static int pismo_remove(struct i2c_client *client)
+{
+	struct pismo_data *pismo = i2c_get_clientdata(client);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(pismo->dev); i++)
+		platform_device_unregister(pismo->dev[i]);
+
+	kfree(pismo);
+
+	return 0;
+}
+
+static int pismo_probe(struct i2c_client *client,
+		       const struct i2c_device_id *id)
+{
+	struct pismo_pdata *pdata = client->dev.platform_data;
+	struct pismo_eeprom eeprom;
+	struct pismo_data *pismo;
+	int ret, i;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(&client->dev, "functionality mismatch\n");
+		return -EIO;
+	}
+
+	pismo = kzalloc(sizeof(*pismo), GFP_KERNEL);
+	if (!pismo)
+		return -ENOMEM;
+
+	pismo->client = client;
+	if (pdata) {
+		pismo->vpp = pdata->set_vpp;
+		pismo->vpp_data = pdata->vpp_data;
+	}
+	i2c_set_clientdata(client, pismo);
+
+	ret = pismo_eeprom_read(client, &eeprom, 0, sizeof(eeprom));
+	if (ret < 0) {
+		dev_err(&client->dev, "error reading EEPROM: %d\n", ret);
+		goto exit_free;
+	}
+
+	dev_info(&client->dev, "%.15s board found\n", eeprom.board);
+
+	for (i = 0; i < ARRAY_SIZE(eeprom.cs); i++)
+		if (eeprom.cs[i].type != 0xff)
+			pismo_add_one(pismo, i, &eeprom.cs[i],
+				      pdata->cs_addrs[i]);
+
+	return 0;
+
+ exit_free:
+	kfree(pismo);
+	return ret;
+}
+
+static const struct i2c_device_id pismo_id[] = {
+	{ "pismo" },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, pismo_id);
+
+static struct i2c_driver pismo_driver = {
+	.driver	= {
+		.name	= "pismo",
+	},
+	.probe		= pismo_probe,
+	.remove		= pismo_remove,
+	.id_table	= pismo_id,
+};
+
+static int __init pismo_init(void)
+{
+	BUILD_BUG_ON(sizeof(struct pismo_cs_block) != 48);
+	BUILD_BUG_ON(sizeof(struct pismo_eeprom) != 256);
+
+	return i2c_add_driver(&pismo_driver);
+}
+module_init(pismo_init);
+
+static void __exit pismo_exit(void)
+{
+	i2c_del_driver(&pismo_driver);
+}
+module_exit(pismo_exit);
+
+MODULE_AUTHOR("Russell King <linux@arm.linux.org.uk>");
+MODULE_DESCRIPTION("PISMO memory driver");
+MODULE_LICENSE("GPL");