1 files changed, 181 insertions, 87 deletions

diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index 8e375d5fe231..11dc7e69c4fb 100644
--- a/drivers/mtd/nand/s3c2410.c
+++ b/drivers/mtd/nand/s3c2410.c
@@ -74,6 +74,14 @@ static struct nand_ecclayout nand_hw_eccoob = {
 
 struct s3c2410_nand_info;
 
+/**
+ * struct s3c2410_nand_mtd - driver MTD structure
+ * @mtd: The MTD instance to pass to the MTD layer.
+ * @chip: The NAND chip information.
+ * @set: The platform information supplied for this set of NAND chips.
+ * @info: Link back to the hardware information.
+ * @scan_res: The result from calling nand_scan_ident().
+*/
 struct s3c2410_nand_mtd {
         struct mtd_info                 mtd;
         struct nand_chip                chip;
@@ -90,6 +98,21 @@ enum s3c_cpu_type {
 
 /* overview of the s3c2410 nand state */
 
+/**
+ * struct s3c2410_nand_info - NAND controller state.
+ * @mtds: An array of MTD instances on this controoler.
+ * @platform: The platform data for this board.
+ * @device: The platform device we bound to.
+ * @area: The IO area resource that came from request_mem_region().
+ * @clk: The clock resource for this controller.
+ * @regs: The area mapped for the hardware registers described by @area.
+ * @sel_reg: Pointer to the register controlling the NAND selection.
+ * @sel_bit: The bit in @sel_reg to select the NAND chip.
+ * @mtd_count: The number of MTDs created from this controller.
+ * @save_sel: The contents of @sel_reg to be saved over suspend.
+ * @clk_rate: The clock rate from @clk.
+ * @cpu_type: The exact type of this controller.
+ */
 struct s3c2410_nand_info {
         /* mtd info */
         struct nand_hw_control          controller;
@@ -145,12 +168,19 @@ static inline int allow_clk_stop(struct s3c2410_nand_info *info)
 
 #define NS_IN_KHZ 1000000
 
+/**
+ * s3c_nand_calc_rate - calculate timing data.
+ * @wanted: The cycle time in nanoseconds.
+ * @clk: The clock rate in kHz.
+ * @max: The maximum divider value.
+ *
+ * Calculate the timing value from the given parameters.
+ */
 static int s3c_nand_calc_rate(int wanted, unsigned long clk, int max)
 {
         int result;
 
-        result = (wanted * clk) / NS_IN_KHZ;
-        result++;
+        result = DIV_ROUND_UP((wanted * clk), NS_IN_KHZ);
 
         pr_debug("result %d from %ld, %d\n", result, clk, wanted);
 
@@ -169,13 +199,21 @@ static int s3c_nand_calc_rate(int wanted, unsigned long clk, int max)
 
 /* controller setup */
 
+/**
+ * s3c2410_nand_setrate - setup controller timing information.
+ * @info: The controller instance.
+ *
+ * Given the information supplied by the platform, calculate and set
+ * the necessary timing registers in the hardware to generate the
+ * necessary timing cycles to the hardware.
+ */
 static int s3c2410_nand_setrate(struct s3c2410_nand_info *info)
 {
         struct s3c2410_platform_nand *plat = info->platform;
         int tacls_max = (info->cpu_type == TYPE_S3C2412) ? 8 : 4;
         int tacls, twrph0, twrph1;
         unsigned long clkrate = clk_get_rate(info->clk);
-        unsigned long set, cfg, mask;
+        unsigned long uninitialized_var(set), cfg, uninitialized_var(mask);
         unsigned long flags;
 
         /* calculate the timing information for the controller */
@@ -215,9 +253,9 @@ static int s3c2410_nand_setrate(struct s3c2410_nand_info *info)
 
         case TYPE_S3C2440:
         case TYPE_S3C2412:
-                mask = (S3C2410_NFCONF_TACLS(tacls_max - 1) |
-                        S3C2410_NFCONF_TWRPH0(7) |
-                        S3C2410_NFCONF_TWRPH1(7));
+                mask = (S3C2440_NFCONF_TACLS(tacls_max - 1) |
+                        S3C2440_NFCONF_TWRPH0(7) |
+                        S3C2440_NFCONF_TWRPH1(7));
 
                 set = S3C2440_NFCONF_TACLS(tacls - 1);
                 set |= S3C2440_NFCONF_TWRPH0(twrph0 - 1);
@@ -225,14 +263,9 @@ static int s3c2410_nand_setrate(struct s3c2410_nand_info *info)
                 break;
 
         default:
-                /* keep compiler happy */
-                mask = 0;
-                set = 0;
                 BUG();
         }
 
-        dev_dbg(info->device, "NF_CONF is 0x%lx\n", cfg);
-
         local_irq_save(flags);
 
         cfg = readl(info->regs + S3C2410_NFCONF);
@@ -242,9 +275,18 @@ static int s3c2410_nand_setrate(struct s3c2410_nand_info *info)
 
         local_irq_restore(flags);
 
+        dev_dbg(info->device, "NF_CONF is 0x%lx\n", cfg);
+
         return 0;
 }
 
+/**
+ * s3c2410_nand_inithw - basic hardware initialisation
+ * @info: The hardware state.
+ *
+ * Do the basic initialisation of the hardware, using s3c2410_nand_setrate()
+ * to setup the hardware access speeds and set the controller to be enabled.
+*/
 static int s3c2410_nand_inithw(struct s3c2410_nand_info *info)
 {
         int ret;
@@ -268,8 +310,19 @@ static int s3c2410_nand_inithw(struct s3c2410_nand_info *info)
         return 0;
 }
 
-/* select chip */
-
+/**
+ * s3c2410_nand_select_chip - select the given nand chip
+ * @mtd: The MTD instance for this chip.
+ * @chip: The chip number.
+ *
+ * This is called by the MTD layer to either select a given chip for the
+ * @mtd instance, or to indicate that the access has finished and the
+ * chip can be de-selected.
+ *
+ * The routine ensures that the nFCE line is correctly setup, and any
+ * platform specific selection code is called to route nFCE to the specific
+ * chip.
+ */
 static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
 {
         struct s3c2410_nand_info *info;
@@ -530,7 +583,16 @@ static void s3c2410_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
 static void s3c2440_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
 {
         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
-        readsl(info->regs + S3C2440_NFDATA, buf, len / 4);
+
+        readsl(info->regs + S3C2440_NFDATA, buf, len >> 2);
+
+        /* cleanup if we've got less than a word to do */
+        if (len & 3) {
+                buf += len & ~3;
+
+                for (; len & 3; len--)
+                        *buf++ = readb(info->regs + S3C2440_NFDATA);
+        }
 }
 
 static void s3c2410_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
@@ -542,7 +604,16 @@ static void s3c2410_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int
 static void s3c2440_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
 {
         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
-        writesl(info->regs + S3C2440_NFDATA, buf, len / 4);
+
+        writesl(info->regs + S3C2440_NFDATA, buf, len >> 2);
+
+        /* cleanup any fractional write */
+        if (len & 3) {
+                buf += len & ~3;
+
+                for (; len & 3; len--, buf++)
+                        writeb(*buf, info->regs + S3C2440_NFDATA);
+        }
 }
 
 /* cpufreq driver support */
@@ -593,7 +664,7 @@ static inline void s3c2410_nand_cpufreq_deregister(struct s3c2410_nand_info *inf
 
 /* device management functions */
 
-static int s3c2410_nand_remove(struct platform_device *pdev)
+static int s3c24xx_nand_remove(struct platform_device *pdev)
 {
         struct s3c2410_nand_info *info = to_nand_info(pdev);
 
@@ -645,17 +716,31 @@ static int s3c2410_nand_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_MTD_PARTITIONS
+const char *part_probes[] = { "cmdlinepart", NULL };
 static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
                                       struct s3c2410_nand_mtd *mtd,
                                       struct s3c2410_nand_set *set)
 {
+        struct mtd_partition *part_info;
+        int nr_part = 0;
+
         if (set == NULL)
                 return add_mtd_device(&mtd->mtd);
 
-        if (set->nr_partitions > 0 && set->partitions != NULL) {
-                return add_mtd_partitions(&mtd->mtd, set->partitions, set->nr_partitions);
+        if (set->nr_partitions == 0) {
+                mtd->mtd.name = set->name;
+                nr_part = parse_mtd_partitions(&mtd->mtd, part_probes,
+                                                &part_info, 0);
+        } else {
+                if (set->nr_partitions > 0 && set->partitions != NULL) {
+                        nr_part = set->nr_partitions;
+                        part_info = set->partitions;
+                }
         }
 
+        if (nr_part > 0 && part_info)
+                return add_mtd_partitions(&mtd->mtd, part_info, nr_part);
+
         return add_mtd_device(&mtd->mtd);
 }
 #else
@@ -667,11 +752,16 @@ static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
 }
 #endif
 
-/* s3c2410_nand_init_chip
+/**
+ * s3c2410_nand_init_chip - initialise a single instance of an chip
+ * @info: The base NAND controller the chip is on.
+ * @nmtd: The new controller MTD instance to fill in.
+ * @set: The information passed from the board specific platform data.
  *
- * init a single instance of an chip
-*/
-
+ * Initialise the given @nmtd from the information in @info and @set. This
+ * readies the structure for use with the MTD layer functions by ensuring
+ * all pointers are setup and the necessary control routines selected.
+ */
 static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
                                    struct s3c2410_nand_mtd *nmtd,
                                    struct s3c2410_nand_set *set)
@@ -757,14 +847,40 @@ static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
 
         if (set->disable_ecc)
                 chip->ecc.mode  = NAND_ECC_NONE;
+
+        switch (chip->ecc.mode) {
+        case NAND_ECC_NONE:
+                dev_info(info->device, "NAND ECC disabled\n");
+                break;
+        case NAND_ECC_SOFT:
+                dev_info(info->device, "NAND soft ECC\n");
+                break;
+        case NAND_ECC_HW:
+                dev_info(info->device, "NAND hardware ECC\n");
+                break;
+        default:
+                dev_info(info->device, "NAND ECC UNKNOWN\n");
+                break;
+        }
+
+        /* If you use u-boot BBT creation code, specifying this flag will
+         * let the kernel fish out the BBT from the NAND, and also skip the
+         * full NAND scan that can take 1/2s or so. Little things... */
+        if (set->flash_bbt)
+                chip->options |= NAND_USE_FLASH_BBT | NAND_SKIP_BBTSCAN;
 }
 
-/* s3c2410_nand_update_chip
+/**
+ * s3c2410_nand_update_chip - post probe update
+ * @info: The controller instance.
+ * @nmtd: The driver version of the MTD instance.
  *
- * post-probe chip update, to change any items, such as the
- * layout for large page nand
- */
-
+ * This routine is called after the chip probe has succesfully completed
+ * and the relevant per-chip information updated. This call ensure that
+ * we update the internal state accordingly.
+ *
+ * The internal state is currently limited to the ECC state information.
+*/
 static void s3c2410_nand_update_chip(struct s3c2410_nand_info *info,
                                      struct s3c2410_nand_mtd *nmtd)
 {
@@ -773,33 +889,33 @@ static void s3c2410_nand_update_chip(struct s3c2410_nand_info *info,
         dev_dbg(info->device, "chip %p => page shift %d\n",
                 chip, chip->page_shift);
 
-        if (hardware_ecc) {
+        if (chip->ecc.mode != NAND_ECC_HW)
+                return;
+
                 /* change the behaviour depending on wether we are using
                  * the large or small page nand device */
 
-                if (chip->page_shift > 10) {
-                        chip->ecc.size      = 256;
-                        chip->ecc.bytes     = 3;
-                } else {
-                        chip->ecc.size      = 512;
-                        chip->ecc.bytes     = 3;
-                        chip->ecc.layout    = &nand_hw_eccoob;
-                }
+        if (chip->page_shift > 10) {
+                chip->ecc.size      = 256;
+                chip->ecc.bytes     = 3;
+        } else {
+                chip->ecc.size      = 512;
+                chip->ecc.bytes     = 3;
+                chip->ecc.layout    = &nand_hw_eccoob;
         }
 }
 
-/* s3c2410_nand_probe
+/* s3c24xx_nand_probe
  *
  * called by device layer when it finds a device matching
  * one our driver can handled. This code checks to see if
  * it can allocate all necessary resources then calls the
  * nand layer to look for devices
 */
-
-static int s3c24xx_nand_probe(struct platform_device *pdev,
-                              enum s3c_cpu_type cpu_type)
+static int s3c24xx_nand_probe(struct platform_device *pdev)
 {
         struct s3c2410_platform_nand *plat = to_nand_plat(pdev);
+        enum s3c_cpu_type cpu_type; 
         struct s3c2410_nand_info *info;
         struct s3c2410_nand_mtd *nmtd;
         struct s3c2410_nand_set *sets;
@@ -809,6 +925,8 @@ static int s3c24xx_nand_probe(struct platform_device *pdev,
         int nr_sets;
         int setno;
 
+        cpu_type = platform_get_device_id(pdev)->driver_data;
+
         pr_debug("s3c2410_nand_probe(%p)\n", pdev);
 
         info = kmalloc(sizeof(*info), GFP_KERNEL);
@@ -922,7 +1040,7 @@ static int s3c24xx_nand_probe(struct platform_device *pdev,
         return 0;
 
  exit_error:
-        s3c2410_nand_remove(pdev);
+        s3c24xx_nand_remove(pdev);
 
         if (err == 0)
                 err = -EINVAL;
@@ -983,50 +1101,33 @@ static int s3c24xx_nand_resume(struct platform_device *dev)
 
 /* driver device registration */
 
-static int s3c2410_nand_probe(struct platform_device *dev)
-{
-        return s3c24xx_nand_probe(dev, TYPE_S3C2410);
-}
-
-static int s3c2440_nand_probe(struct platform_device *dev)
-{
-        return s3c24xx_nand_probe(dev, TYPE_S3C2440);
-}
-
-static int s3c2412_nand_probe(struct platform_device *dev)
-{
-        return s3c24xx_nand_probe(dev, TYPE_S3C2412);
-}
-
-static struct platform_driver s3c2410_nand_driver = {
-        .probe          = s3c2410_nand_probe,
-        .remove         = s3c2410_nand_remove,
-        .suspend        = s3c24xx_nand_suspend,
-        .resume         = s3c24xx_nand_resume,
-        .driver         = {
-                .name   = "s3c2410-nand",
-                .owner  = THIS_MODULE,
+static struct platform_device_id s3c24xx_driver_ids[] = {
+        {
+                .name           = "s3c2410-nand",
+                .driver_data    = TYPE_S3C2410,
+        }, {
+                .name           = "s3c2440-nand",
+                .driver_data    = TYPE_S3C2440,
+        }, {
+                .name           = "s3c2412-nand",
+                .driver_data    = TYPE_S3C2412,
+        }, {
+                .name           = "s3c6400-nand",
+                .driver_data    = TYPE_S3C2412, /* compatible with 2412 */
         },
+        { }
 };
 
-static struct platform_driver s3c2440_nand_driver = {
-        .probe          = s3c2440_nand_probe,
-        .remove         = s3c2410_nand_remove,
-        .suspend        = s3c24xx_nand_suspend,
-        .resume         = s3c24xx_nand_resume,
-        .driver         = {
-                .name   = "s3c2440-nand",
-                .owner  = THIS_MODULE,
-        },
-};
+MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
 
-static struct platform_driver s3c2412_nand_driver = {
-        .probe          = s3c2412_nand_probe,
-        .remove         = s3c2410_nand_remove,
+static struct platform_driver s3c24xx_nand_driver = {
+        .probe          = s3c24xx_nand_probe,
+        .remove         = s3c24xx_nand_remove,
         .suspend        = s3c24xx_nand_suspend,
         .resume         = s3c24xx_nand_resume,
+        .id_table       = s3c24xx_driver_ids,
         .driver         = {
-                .name   = "s3c2412-nand",
+                .name   = "s3c24xx-nand",
                 .owner  = THIS_MODULE,
         },
 };
@@ -1035,16 +1136,12 @@ static int __init s3c2410_nand_init(void)
 {
         printk("S3C24XX NAND Driver, (c) 2004 Simtec Electronics\n");
 
-        platform_driver_register(&s3c2412_nand_driver);
-        platform_driver_register(&s3c2440_nand_driver);
-        return platform_driver_register(&s3c2410_nand_driver);
+        return platform_driver_register(&s3c24xx_nand_driver);
 }
 
 static void __exit s3c2410_nand_exit(void)
 {
-        platform_driver_unregister(&s3c2412_nand_driver);
-        platform_driver_unregister(&s3c2440_nand_driver);
-        platform_driver_unregister(&s3c2410_nand_driver);
+        platform_driver_unregister(&s3c24xx_nand_driver);
 }
 
 module_init(s3c2410_nand_init);
@@ -1053,6 +1150,3 @@ module_exit(s3c2410_nand_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
 MODULE_DESCRIPTION("S3C24XX MTD NAND driver");
-MODULE_ALIAS("platform:s3c2410-nand");
-MODULE_ALIAS("platform:s3c2412-nand");
-MODULE_ALIAS("platform:s3c2440-nand");