[RFC PATCH 01/10] mtd: nand: omap: Use a single hardware controller instance

From: Roger Quadros
Date: Wed Jul 09 2014 - 08:41:54 EST


There is only one NAND controller (ECC generator) that needs to be
shared among multiple devices. So point nand_chip->hwcontrol to
a single omap_hw_controller instance.
This way the NAND base driver can take care of serializing access
to this single controller (via nand_chip->controller->lock)
when multiple NAND devices are present.

Signed-off-by: Roger Quadros <rogerq@xxxxxx>
---
drivers/mtd/nand/omap2.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
index f0ed92e..5b8739c 100644
--- a/drivers/mtd/nand/omap2.c
+++ b/drivers/mtd/nand/omap2.c
@@ -149,8 +149,9 @@ static u_char bch4_vector[] = {0x00, 0x6b, 0x31, 0xdd, 0x41, 0xbc, 0x10};
/* oob info generated runtime depending on ecc algorithm and layout selected */
static struct nand_ecclayout omap_oobinfo;

+static struct nand_hw_control omap_hw_controller;
+
struct omap_nand_info {
- struct nand_hw_control controller;
struct omap_nand_platform_data *pdata;
struct mtd_info mtd;
struct nand_chip nand;
@@ -1649,9 +1650,6 @@ static int omap_nand_probe(struct platform_device *pdev)

platform_set_drvdata(pdev, info);

- spin_lock_init(&info->controller.lock);
- init_waitqueue_head(&info->controller.wq);
-
info->pdev = pdev;
info->gpmc_cs = pdata->cs;
info->reg = pdata->reg;
@@ -1672,7 +1670,13 @@ static int omap_nand_probe(struct platform_device *pdev)

info->phys_base = res->start;

- nand_chip->controller = &info->controller;
+ /*
+ * There is only one NAND controller (ECC generator) that needs to be
+ * shared among multiple devices. The NAND base driver takes care of
+ * serializing access to this single controller when multiple NAND
+ * devices are present.
+ */
+ nand_chip->hwcontrol = omap_hw_controller;

nand_chip->IO_ADDR_W = nand_chip->IO_ADDR_R;
nand_chip->cmd_ctrl = omap_hwcontrol;
--
1.8.3.2

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