[RFC PATCH 11/16] mtd: nand: omap: Move NAND write protect code from GPMC to NAND driver

From: Roger Quadros
Date: Wed May 21 2014 - 07:25:19 EST


The write protect (WP) pin is only used for NAND devices. So move
the code into the NAND driver.

Get rid of gpmc_configure() and gpmc_write_reg() as they are no longer
used.

Signed-off-by: Roger Quadros <rogerq@xxxxxx>
---
arch/arm/mach-omap2/gpmc.c | 42 ----------------------------
arch/arm/mach-omap2/gpmc.h | 4 ---
drivers/mtd/nand/omap2.c | 23 +++++++++++++++
include/linux/platform_data/mtd-nand-omap2.h | 1 +
4 files changed, 24 insertions(+), 46 deletions(-)

diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
index 4207dc9..132f786 100644
--- a/arch/arm/mach-omap2/gpmc.c
+++ b/arch/arm/mach-omap2/gpmc.c
@@ -154,11 +154,6 @@ static void __iomem *gpmc_base;

static struct clk *gpmc_l3_clk;

-static void gpmc_write_reg(int idx, u32 val)
-{
- __raw_writel(val, gpmc_base + idx);
-}
-
static u32 gpmc_read_reg(int idx)
{
return __raw_readl(gpmc_base + idx);
@@ -597,35 +592,6 @@ void gpmc_cs_free(int cs)
}
EXPORT_SYMBOL(gpmc_cs_free);

-/**
- * gpmc_configure - write request to configure gpmc
- * @cmd: command type
- * @wval: value to write
- * @return status of the operation
- */
-int gpmc_configure(int cmd, int wval)
-{
- u32 regval;
-
- switch (cmd) {
- case GPMC_CONFIG_WP:
- regval = gpmc_read_reg(GPMC_CONFIG);
- if (wval)
- regval &= ~GPMC_CONFIG_WRITEPROTECT; /* WP is ON */
- else
- regval |= GPMC_CONFIG_WRITEPROTECT; /* WP is OFF */
- gpmc_write_reg(GPMC_CONFIG, regval);
- break;
-
- default:
- pr_err("%s: command not supported\n", __func__);
- return -EINVAL;
- }
-
- return 0;
-}
-EXPORT_SYMBOL(gpmc_configure);
-
static void gpmc_mem_exit(void)
{
int cs;
@@ -1471,7 +1437,6 @@ static int gpmc_nand_setup(struct platform_device *parent_pdev,
struct gpmc_settings *settings)
{
struct resource *res;
- int rc;
struct resource *res_mem;

/* GPMC register space */
@@ -1486,13 +1451,6 @@ static int gpmc_nand_setup(struct platform_device *parent_pdev,
res[2].start = gpmc_irq;

settings->device_nand = true;
- /*
- * Not sure why WP is explicitly turned OFF. we just moved it here
- * as is from mach-omap2/gpmc-nand.c
- */
- rc = gpmc_configure(GPMC_CONFIG_WP, 0);
- if (rc < 0)
- return rc;

return 0;
}
diff --git a/arch/arm/mach-omap2/gpmc.h b/arch/arm/mach-omap2/gpmc.h
index 05974f0..8ebadf5 100644
--- a/arch/arm/mach-omap2/gpmc.h
+++ b/arch/arm/mach-omap2/gpmc.h
@@ -22,9 +22,6 @@
#define GPMC_CS_CONFIG6 0x14
#define GPMC_CS_CONFIG7 0x18

-/* Control Commands */
-#define GPMC_CONFIG_WP 0x00000005
-
/* ECC commands */
#define GPMC_ECC_READ 0 /* Reset Hardware ECC for read */
#define GPMC_ECC_WRITE 1 /* Reset Hardware ECC for write */
@@ -57,7 +54,6 @@

#define GPMC_DEVICETYPE_NOR 0
#define GPMC_DEVICETYPE_NAND 2
-#define GPMC_CONFIG_WRITEPROTECT 0x00000010
#define WR_RD_PIN_MONITORING 0x00600000
#define GPMC_IRQ_FIFOEVENTENABLE 0x01
#define GPMC_IRQ_COUNT_EVENT 0x02
diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
index 7d12d92..fee0458 100644
--- a/drivers/mtd/nand/omap2.c
+++ b/drivers/mtd/nand/omap2.c
@@ -140,6 +140,9 @@
#define GPMC_IRQ_FIFOEVENT BIT(0)
#define GPMC_IRQ_TERMCOUNT BIT(1)

+/* GPMC_CONFIG register bits */
+#define GPMC_CONFIG_WRITEPROTECT BIT(4)
+
/* GPMC register offsets */
#define GPMC_REVISION 0x00
#define GPMC_SYSCONFIG 0x10
@@ -206,6 +209,22 @@ struct omap_nand_info {
};

/**
+ * omap_nand_writeprotect - Control the WP line to the NAND chip
+ */
+static void omap_nand_writeprotect(struct omap_nand_info *info, bool on)
+{
+ u32 val;
+
+ val = readl(info->reg.gpmc_config);
+ if (on)
+ val |= GPMC_CONFIG_WRITEPROTECT;
+ else
+ val &= GPMC_CONFIG_WRITEPROTECT;
+
+ writel(val, info->reg.gpmc_config);
+}
+
+/**
* omap_prefetch_enable - configures and starts prefetch transfer
* @cs: cs (chip select) number
* @fifo_th: fifo threshold to be used for read/ write
@@ -1622,6 +1641,7 @@ static void gpmc_update_nand_reg(struct omap_nand_info *info)
int cs = info->gpmc_cs;
void __iomem *gpmc_base = info->gpmc_base;

+ reg->gpmc_config = gpmc_base + GPMC_CONFIG;
reg->gpmc_status = gpmc_base + GPMC_STATUS;
reg->gpmc_irqstatus = gpmc_base + GPMC_IRQSTATUS;
reg->gpmc_irqenable = gpmc_base + GPMC_IRQENABLE;
@@ -2029,6 +2049,9 @@ static int omap_nand_probe(struct platform_device *pdev)
goto return_error;
}

+ /* turn off write protect */
+ omap_nand_writeprotect(info, false);
+
/* second phase scan */
if (nand_scan_tail(mtd)) {
err = -ENXIO;
diff --git a/include/linux/platform_data/mtd-nand-omap2.h b/include/linux/platform_data/mtd-nand-omap2.h
index b71cfbd..62a855e 100644
--- a/include/linux/platform_data/mtd-nand-omap2.h
+++ b/include/linux/platform_data/mtd-nand-omap2.h
@@ -34,6 +34,7 @@ enum omap_ecc {
};

struct gpmc_nand_regs {
+ void __iomem *gpmc_config;
void __iomem *gpmc_status;
void __iomem *gpmc_irqstatus;
void __iomem *gpmc_irqenable;
--
1.8.3.2

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