MTD: nand: make au1550nd.c a platform_driver

Transform the au1550nd.c driver into a platform_driver and hook it
up in the PB1550 board (gen_nand works fine on the DB1550, but since
I don't have a PB1550 to test this driver stays for now).

Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
Cc: linux-mtd@lists.infradead.org
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2875/
Patchwork: https://patchwork.linux-mips.org/patch/3160/
Acked-by: Artem Bityutskiy <dedekind1@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

3 files changed, 205 insertions, 175 deletions

diff --git a/arch/mips/alchemy/devboards/pb1550.c b/arch/mips/alchemy/devboards/pb1550.c
index e4a00a56a20..b37e7de8d92 100644
--- a/arch/mips/alchemy/devboards/pb1550.c
+++ b/arch/mips/alchemy/devboards/pb1550.c
@@ -24,6 +24,7 @@
 #include <linux/platform_device.h>
 #include <asm/mach-au1x00/au1000.h>
 #include <asm/mach-au1x00/au1xxx_dbdma.h>
+#include <asm/mach-au1x00/au1550nd.h>
 #include <asm/mach-au1x00/gpio.h>
 #include <asm/mach-db1x00/bcsr.h>
 #include "platform.h"
@@ -131,6 +132,67 @@ static struct platform_device pb1550_i2c_dev = {
         .resource       = au1550_psc2_res,
 };
 
+static struct mtd_partition pb1550_nand_parts[] = {
+        [0] = {
+                .name   = "NAND FS 0",
+                .offset = 0,
+                .size   = 8 * 1024 * 1024,
+        },
+        [1] = {
+                .name   = "NAND FS 1",
+                .offset = MTDPART_OFS_APPEND,
+                .size   = MTDPART_SIZ_FULL,
+        },
+};
+
+static struct au1550nd_platdata pb1550_nand_pd = {
+        .parts          = pb1550_nand_parts,
+        .num_parts      = ARRAY_SIZE(pb1550_nand_parts),
+        .devwidth       = 0,    /* x8 NAND default, needs fixing up */
+};
+
+static struct resource pb1550_nand_res[] = {
+        [0] = {
+                .start  = 0x20000000,
+                .end    = 0x20000fff,
+                .flags  = IORESOURCE_MEM,
+        },
+};
+
+static struct platform_device pb1550_nand_dev = {
+        .name           = "au1550-nand",
+        .id             = -1,
+        .resource       = pb1550_nand_res,
+        .num_resources  = ARRAY_SIZE(pb1550_nand_res),
+        .dev            = {
+                .platform_data  = &pb1550_nand_pd,
+        },
+};
+
+static void __init pb1550_nand_setup(void)
+{
+        int boot_swapboot = (au_readl(MEM_STSTAT) & (0x7 << 1)) |
+                            ((bcsr_read(BCSR_STATUS) >> 6) & 0x1);
+
+        switch (boot_swapboot) {
+        case 0:
+        case 2:
+        case 8:
+        case 0xC:
+        case 0xD:
+                /* x16 NAND Flash */
+                pb1550_nand_pd.devwidth = 1;
+                /* fallthrough */
+        case 1:
+        case 9:
+        case 3:
+        case 0xE:
+        case 0xF:
+                /* x8 NAND, already set up */
+                platform_device_register(&pb1550_nand_dev);
+        }
+}
+
 static int __init pb1550_dev_init(void)
 {
         int swapped;
@@ -168,6 +230,10 @@ static int __init pb1550_dev_init(void)
                 AU1000_PCMCIA_IO_PHYS_ADDR   + 0x008010000 - 1,
                 AU1550_GPIO201_205_INT, AU1550_GPIO1_INT, 0, 0, 1);
 
+        /* NAND setup */
+        gpio_direction_input(206);      /* GPIO206 high */
+        pb1550_nand_setup();
+
         swapped = bcsr_read(BCSR_STATUS) & BCSR_STATUS_PB1550_SWAPBOOT;
         db1x_register_norflash(128 * 1024 * 1024, 4, swapped);
         platform_device_register(&pb1550_pci_host);
diff --git a/arch/mips/include/asm/mach-au1x00/au1550nd.h b/arch/mips/include/asm/mach-au1x00/au1550nd.h
new file mode 100644
index 00000000000..ad4c0a03afe
--- /dev/null
+++ b/arch/mips/include/asm/mach-au1x00/au1550nd.h
@@ -0,0 +1,16 @@
+/*
+ * platform data for the Au1550 NAND driver
+ */
+
+#ifndef _AU1550ND_H_
+#define _AU1550ND_H_
+
+#include <linux/mtd/partitions.h>
+
+struct au1550nd_platdata {
+        struct mtd_partition *parts;
+        int num_parts;
+        int devwidth;   /* 0 = 8bit device, 1 = 16bit device */
+};
+
+#endif
diff --git a/drivers/mtd/nand/au1550nd.c b/drivers/mtd/nand/au1550nd.c
index 7dd3700f230..73abbc3e093 100644
--- a/drivers/mtd/nand/au1550nd.c
+++ b/drivers/mtd/nand/au1550nd.c
@@ -17,35 +17,19 @@
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/nand.h>
 #include <linux/mtd/partitions.h>
+#include <linux/platform_device.h>
 #include <asm/io.h>
+#include <asm/mach-au1x00/au1000.h>
+#include <asm/mach-au1x00/au1550nd.h>
 
-#ifdef CONFIG_MIPS_PB1550
-#include <asm/mach-pb1x00/pb1550.h>
-#elif defined(CONFIG_MIPS_DB1550)
-#include <asm/mach-db1x00/db1x00.h>
-#endif
-#include <asm/mach-db1x00/bcsr.h>
 
-/*
- * MTD structure for NAND controller
- */
-static struct mtd_info *au1550_mtd = NULL;
-static void __iomem *p_nand;
-static int nand_width = 1;      /* default x8 */
-static void (*au1550_write_byte)(struct mtd_info *, u_char);
+struct au1550nd_ctx {
+        struct mtd_info info;
+        struct nand_chip chip;
 
-/*
- * Define partitions for flash device
- */
-static const struct mtd_partition partition_info[] = {
-        {
-         .name = "NAND FS 0",
-         .offset = 0,
-         .size = 8 * 1024 * 1024},
-        {
-         .name = "NAND FS 1",
-         .offset = MTDPART_OFS_APPEND,
-         .size = MTDPART_SIZ_FULL}
+        int cs;
+        void __iomem *base;
+        void (*write_byte)(struct mtd_info *, u_char);
 };
 
 /**
@@ -259,24 +243,25 @@ static int au_verify_buf16(struct mtd_info *mtd, const u_char *buf, int len)
 
 static void au1550_hwcontrol(struct mtd_info *mtd, int cmd)
 {
-        register struct nand_chip *this = mtd->priv;
+        struct au1550nd_ctx *ctx = container_of(mtd, struct au1550nd_ctx, info);
+        struct nand_chip *this = mtd->priv;
 
         switch (cmd) {
 
         case NAND_CTL_SETCLE:
-                this->IO_ADDR_W = p_nand + MEM_STNAND_CMD;
+                this->IO_ADDR_W = ctx->base + MEM_STNAND_CMD;
                 break;
 
         case NAND_CTL_CLRCLE:
-                this->IO_ADDR_W = p_nand + MEM_STNAND_DATA;
+                this->IO_ADDR_W = ctx->base + MEM_STNAND_DATA;
                 break;
 
         case NAND_CTL_SETALE:
-                this->IO_ADDR_W = p_nand + MEM_STNAND_ADDR;
+                this->IO_ADDR_W = ctx->base + MEM_STNAND_ADDR;
                 break;
 
         case NAND_CTL_CLRALE:
-                this->IO_ADDR_W = p_nand + MEM_STNAND_DATA;
+                this->IO_ADDR_W = ctx->base + MEM_STNAND_DATA;
                 /* FIXME: Nobody knows why this is necessary,
                  * but it works only that way */
                 udelay(1);
@@ -284,7 +269,7 @@ static void au1550_hwcontrol(struct mtd_info *mtd, int cmd)
 
         case NAND_CTL_SETNCE:
                 /* assert (force assert) chip enable */
-                au_writel((1 << (4 + NAND_CS)), MEM_STNDCTL);
+                au_writel((1 << (4 + ctx->cs)), MEM_STNDCTL);
                 break;
 
         case NAND_CTL_CLRNCE:
@@ -331,9 +316,10 @@ static void au1550_select_chip(struct mtd_info *mtd, int chip)
  */
 static void au1550_command(struct mtd_info *mtd, unsigned command, int column, int page_addr)
 {
-        register struct nand_chip *this = mtd->priv;
+        struct au1550nd_ctx *ctx = container_of(mtd, struct au1550nd_ctx, info);
+        struct nand_chip *this = mtd->priv;
         int ce_override = 0, i;
-        ulong flags;
+        unsigned long flags = 0;
 
         /* Begin command latch cycle */
         au1550_hwcontrol(mtd, NAND_CTL_SETCLE);
@@ -354,9 +340,9 @@ static void au1550_command(struct mtd_info *mtd, unsigned command, int column, i
                         column -= 256;
                         readcmd = NAND_CMD_READ1;
                 }
-                au1550_write_byte(mtd, readcmd);
+                ctx->write_byte(mtd, readcmd);
         }
-        au1550_write_byte(mtd, command);
+        ctx->write_byte(mtd, command);
 
         /* Set ALE and clear CLE to start address cycle */
         au1550_hwcontrol(mtd, NAND_CTL_CLRCLE);
@@ -369,10 +355,10 @@ static void au1550_command(struct mtd_info *mtd, unsigned command, int column, i
                         /* Adjust columns for 16 bit buswidth */
                         if (this->options & NAND_BUSWIDTH_16)
                                 column >>= 1;
-                        au1550_write_byte(mtd, column);
+                        ctx->write_byte(mtd, column);
                 }
                 if (page_addr != -1) {
-                        au1550_write_byte(mtd, (u8)(page_addr & 0xff));
+                        ctx->write_byte(mtd, (u8)(page_addr & 0xff));
 
                         if (command == NAND_CMD_READ0 ||
                             command == NAND_CMD_READ1 ||
@@ -390,11 +376,12 @@ static void au1550_command(struct mtd_info *mtd, unsigned command, int column, i
                                 au1550_hwcontrol(mtd, NAND_CTL_SETNCE);
                         }
 
-                        au1550_write_byte(mtd, (u8)(page_addr >> 8));
+                        ctx->write_byte(mtd, (u8)(page_addr >> 8));
 
                         /* One more address cycle for devices > 32MiB */
                         if (this->chipsize > (32 << 20))
-                                au1550_write_byte(mtd, (u8)((page_addr >> 16) & 0x0f));
+                                ctx->write_byte(mtd,
+                                                ((page_addr >> 16) & 0x0f));
                 }
                 /* Latch in address */
                 au1550_hwcontrol(mtd, NAND_CTL_CLRALE);
@@ -440,121 +427,79 @@ static void au1550_command(struct mtd_info *mtd, unsigned command, int column, i
         while(!this->dev_ready(mtd));
 }
 
-
-/*
- * Main initialization routine
- */
-static int __init au1xxx_nand_init(void)
+static int __devinit find_nand_cs(unsigned long nand_base)
 {
-        struct nand_chip *this;
-        u16 boot_swapboot = 0;  /* default value */
-        int retval;
-        u32 mem_staddr;
-        u32 nand_phys;
-
-        /* Allocate memory for MTD device structure and private data */
-        au1550_mtd = kzalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
-        if (!au1550_mtd) {
-                printk("Unable to allocate NAND MTD dev structure.\n");
-                return -ENOMEM;
-        }
-
-        /* Get pointer to private data */
-        this = (struct nand_chip *)(&au1550_mtd[1]);
-
-        /* Link the private data with the MTD structure */
-        au1550_mtd->priv = this;
-        au1550_mtd->owner = THIS_MODULE;
-
+        void __iomem *base =
+                        (void __iomem *)KSEG1ADDR(AU1000_STATIC_MEM_PHYS_ADDR);
+        unsigned long addr, staddr, start, mask, end;
+        int i;
 
-        /* MEM_STNDCTL: disable ints, disable nand boot */
-        au_writel(0, MEM_STNDCTL);
+        for (i = 0; i < 4; i++) {
+                addr = 0x1000 + (i * 0x10);                     /* CSx */
+                staddr = __raw_readl(base + addr + 0x08);       /* STADDRx */
+                /* figure out the decoded range of this CS */
+                start = (staddr << 4) & 0xfffc0000;
+                mask = (staddr << 18) & 0xfffc0000;
+                end = (start | (start - 1)) & ~(start ^ mask);
+                if ((nand_base >= start) && (nand_base < end))
+                        return i;
+        }
 
-#ifdef CONFIG_MIPS_PB1550
-        /* set gpio206 high */
-        gpio_direction_input(206);
+        return -ENODEV;
+}
 
-        boot_swapboot = (au_readl(MEM_STSTAT) & (0x7 << 1)) | ((bcsr_read(BCSR_STATUS) >> 6) & 0x1);
+static int __devinit au1550nd_probe(struct platform_device *pdev)
+{
+        struct au1550nd_platdata *pd;
+        struct au1550nd_ctx *ctx;
+        struct nand_chip *this;
+        struct resource *r;
+        int ret, cs;
 
-        switch (boot_swapboot) {
-        case 0:
-        case 2:
-        case 8:
-        case 0xC:
-        case 0xD:
-                /* x16 NAND Flash */
-                nand_width = 0;
-                break;
-        case 1:
-        case 9:
-        case 3:
-        case 0xE:
-        case 0xF:
-                /* x8 NAND Flash */
-                nand_width = 1;
-                break;
-        default:
-                printk("Pb1550 NAND: bad boot:swap\n");
-                retval = -EINVAL;
-                goto outmem;
+        pd = pdev->dev.platform_data;
+        if (!pd) {
+                dev_err(&pdev->dev, "missing platform data\n");
+                return -ENODEV;
         }
-#endif
-
-        /* Configure chip-select; normally done by boot code, e.g. YAMON */
-#ifdef NAND_STCFG
-        if (NAND_CS == 0) {
-                au_writel(NAND_STCFG,  MEM_STCFG0);
-                au_writel(NAND_STTIME, MEM_STTIME0);
-                au_writel(NAND_STADDR, MEM_STADDR0);
-        }
-        if (NAND_CS == 1) {
-                au_writel(NAND_STCFG,  MEM_STCFG1);
-                au_writel(NAND_STTIME, MEM_STTIME1);
-                au_writel(NAND_STADDR, MEM_STADDR1);
+
+        ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+        if (!ctx) {
+                dev_err(&pdev->dev, "no memory for NAND context\n");
+                return -ENOMEM;
         }
-        if (NAND_CS == 2) {
-                au_writel(NAND_STCFG,  MEM_STCFG2);
-                au_writel(NAND_STTIME, MEM_STTIME2);
-                au_writel(NAND_STADDR, MEM_STADDR2);
+
+        r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!r) {
+                dev_err(&pdev->dev, "no NAND memory resource\n");
+                ret = -ENODEV;
+                goto out1;
         }
-        if (NAND_CS == 3) {
-                au_writel(NAND_STCFG,  MEM_STCFG3);
-                au_writel(NAND_STTIME, MEM_STTIME3);
-                au_writel(NAND_STADDR, MEM_STADDR3);
+        if (request_mem_region(r->start, resource_size(r), "au1550-nand")) {
+                dev_err(&pdev->dev, "cannot claim NAND memory area\n");
+                ret = -ENOMEM;
+                goto out1;
         }
-#endif
-
-        /* Locate NAND chip-select in order to determine NAND phys address */
-        mem_staddr = 0x00000000;
-        if (((au_readl(MEM_STCFG0) & 0x7) == 0x5) && (NAND_CS == 0))
-                mem_staddr = au_readl(MEM_STADDR0);
-        else if (((au_readl(MEM_STCFG1) & 0x7) == 0x5) && (NAND_CS == 1))
-                mem_staddr = au_readl(MEM_STADDR1);
-        else if (((au_readl(MEM_STCFG2) & 0x7) == 0x5) && (NAND_CS == 2))
-                mem_staddr = au_readl(MEM_STADDR2);
-        else if (((au_readl(MEM_STCFG3) & 0x7) == 0x5) && (NAND_CS == 3))
-                mem_staddr = au_readl(MEM_STADDR3);
-
-        if (mem_staddr == 0x00000000) {
-                printk("Au1xxx NAND: ERROR WITH NAND CHIP-SELECT\n");
-                kfree(au1550_mtd);
-                return 1;
+
+        ctx->base = ioremap_nocache(r->start, 0x1000);
+        if (!ctx->base) {
+                dev_err(&pdev->dev, "cannot remap NAND memory area\n");
+                ret = -ENODEV;
+                goto out2;
         }
-        nand_phys = (mem_staddr << 4) & 0xFFFC0000;
 
-        p_nand = ioremap(nand_phys, 0x1000);
+        this = &ctx->chip;
+        ctx->info.priv = this;
+        ctx->info.owner = THIS_MODULE;
 
-        /* make controller and MTD agree */
-        if (NAND_CS == 0)
-                nand_width = au_readl(MEM_STCFG0) & (1 << 22);
-        if (NAND_CS == 1)
-                nand_width = au_readl(MEM_STCFG1) & (1 << 22);
-        if (NAND_CS == 2)
-                nand_width = au_readl(MEM_STCFG2) & (1 << 22);
-        if (NAND_CS == 3)
-                nand_width = au_readl(MEM_STCFG3) & (1 << 22);
+        /* figure out which CS# r->start belongs to */
+        cs = find_nand_cs(r->start);
+        if (cs < 0) {
+                dev_err(&pdev->dev, "cannot detect NAND chipselect\n");
+                ret = -ENODEV;
+                goto out3;
+        }
+        ctx->cs = cs;
 
-        /* Set address of hardware control function */
         this->dev_ready = au1550_device_ready;
         this->select_chip = au1550_select_chip;
         this->cmdfunc = au1550_command;
@@ -565,54 +510,57 @@ static int __init au1xxx_nand_init(void)
 
         this->options = NAND_NO_AUTOINCR;
 
-        if (!nand_width)
+        if (pd->devwidth)
                 this->options |= NAND_BUSWIDTH_16;
 
-        this->read_byte = (!nand_width) ? au_read_byte16 : au_read_byte;
-        au1550_write_byte = (!nand_width) ? au_write_byte16 : au_write_byte;
+        this->read_byte = (pd->devwidth) ? au_read_byte16 : au_read_byte;
+        ctx->write_byte = (pd->devwidth) ? au_write_byte16 : au_write_byte;
         this->read_word = au_read_word;
-        this->write_buf = (!nand_width) ? au_write_buf16 : au_write_buf;
-        this->read_buf = (!nand_width) ? au_read_buf16 : au_read_buf;
-        this->verify_buf = (!nand_width) ? au_verify_buf16 : au_verify_buf;
-
-        /* Scan to find existence of the device */
-        if (nand_scan(au1550_mtd, 1)) {
-                retval = -ENXIO;
-                goto outio;
+        this->write_buf = (pd->devwidth) ? au_write_buf16 : au_write_buf;
+        this->read_buf = (pd->devwidth) ? au_read_buf16 : au_read_buf;
+        this->verify_buf = (pd->devwidth) ? au_verify_buf16 : au_verify_buf;
+
+        ret = nand_scan(&ctx->info, 1);
+        if (ret) {
+                dev_err(&pdev->dev, "NAND scan failed with %d\n", ret);
+                goto out3;
         }
 
-        /* Register the partitions */
-        mtd_device_register(au1550_mtd, partition_info,
-                            ARRAY_SIZE(partition_info));
+        mtd_device_register(&ctx->info, pd->parts, pd->num_parts);
 
         return 0;
 
- outio:
-        iounmap(p_nand);
-
- outmem:
-        kfree(au1550_mtd);
-        return retval;
+out3:
+        iounmap(ctx->base);
+out2:
+        release_mem_region(r->start, resource_size(r));
+out1:
+        kfree(ctx);
+        return ret;
 }
 
-module_init(au1xxx_nand_init);
-
-/*
- * Clean up routine
- */
-static void __exit au1550_cleanup(void)
+static int __devexit au1550nd_remove(struct platform_device *pdev)
 {
-        /* Release resources, unregister device */
-        nand_release(au1550_mtd);
+        struct au1550nd_ctx *ctx = platform_get_drvdata(pdev);
+        struct resource *r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 
-        /* Free the MTD device structure */
-        kfree(au1550_mtd);
-
-        /* Unmap */
-        iounmap(p_nand);
+        nand_release(&ctx->info);
+        iounmap(ctx->base);
+        release_mem_region(r->start, 0x1000);
+        kfree(ctx);
+        return 0;
 }
 
-module_exit(au1550_cleanup);
+static struct platform_driver au1550nd_driver = {
+        .driver = {
+                .name   = "au1550-nand",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = au1550nd_probe,
+        .remove         = __devexit_p(au1550nd_remove),
+};
+
+module_platform_driver(au1550nd_driver);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Embedded Edge, LLC");