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path: root/drivers/mtd/nand/s3c2410.c
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Diffstat (limited to 'drivers/mtd/nand/s3c2410.c')
-rw-r--r--drivers/mtd/nand/s3c2410.c89
1 files changed, 78 insertions, 11 deletions
diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index b7f0740d842..a2d1c70c522 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;
@@ -145,6 +168,14 @@ 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;
@@ -169,6 +200,14 @@ 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;
@@ -245,6 +284,13 @@ static int s3c2410_nand_setrate(struct s3c2410_nand_info *info)
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 +314,19 @@ 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;
@@ -667,11 +724,16 @@ 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)
@@ -759,12 +821,17 @@ static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
chip->ecc.mode = NAND_ECC_NONE;
}
-/* 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)
{