[PATCH v5 2/2] mtd: nand: sunxi: add reset line support

You're right. This is a copy-n-paste error from the original sunxi-mmc.c file,
which get all the clocks and resets before using them.

20.06.2016, 03:37, "Maxime Ripard" [off-list ref]:

On Mon, Jun 20, 2016 at 12:14:35AM +0800, Icenowy Zheng wrote:

quoted

?The NAND controller on some sun8i chips needs its reset line to be
?deasserted before they can enter working state.

?Signed-off-by: Icenowy Zheng [off-list ref]
?---
?Changes in v2:
???- Corrected the error checking code of reset line.

?Changes in v3:
???- Corrected a more serious error brought in the "fix" of v2.

?Changes in v4:
???- Removed unneeded code block after "else".

?Changes in v5:
???- Added reassertion code in case of initialization error and device
?????remove.

??drivers/mtd/nand/sunxi_nand.c | 27 ++++++++++++++++++++++++---
??1 file changed, 24 insertions(+), 3 deletions(-)

?diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
?index a83a690..3b40186 100644
?--- a/drivers/mtd/nand/sunxi_nand.c
?+++ b/drivers/mtd/nand/sunxi_nand.c
?@@ -39,6 +39,7 @@
??#include <linux/gpio.h>
??#include <linux/interrupt.h>
??#include <linux/iopoll.h>
?+#include <linux/reset.h>

??#define NFC_REG_CTL 0x0000
??#define NFC_REG_ST 0x0004
?@@ -269,6 +270,7 @@ struct sunxi_nfc {
??????????void __iomem *regs;
??????????struct clk *ahb_clk;
??????????struct clk *mod_clk;
?+ struct reset_control *reset;
??????????unsigned long assigned_cs;
??????????unsigned long clk_rate;
??????????struct list_head chips;
?@@ -1871,26 +1873,41 @@ static int sunxi_nfc_probe(struct platform_device *pdev)
??????????if (ret)
??????????????????goto out_ahb_clk_unprepare;

?+ nfc->reset = devm_reset_control_get_optional(dev, "ahb");
?+
?+ if (!IS_ERR(nfc->reset)) {
?+ ret = reset_control_deassert(nfc->reset);
?+ if (ret) {
?+ dev_err(dev, "reset err %d\n", ret);
?+ goto out_mod_clk_unprepare;
?+ }
?+ } else if (PTR_ERR(nfc->reset) != -ENOENT) {
?+ return PTR_ERR(nfc->reset);

You're leaking all the resources here. Please use a goto.

Thanks,
Maxime

--
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com