mtd: nand: sunxi: add reset line support
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 <icenowy@aosc.xyz>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index f582fe4..d2b7457 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
@@ -270,6 +271,7 @@
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;
@@ -2209,15 +2211,27 @@
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) {
+ ret = PTR_ERR(nfc->reset);
+ goto out_mod_clk_unprepare;
+ }
+
ret = sunxi_nfc_rst(nfc);
if (ret)
- goto out_mod_clk_unprepare;
+ goto out_ahb_reset_reassert;
writel(0, nfc->regs + NFC_REG_INT);
ret = devm_request_irq(dev, irq, sunxi_nfc_interrupt,
0, "sunxi-nand", nfc);
if (ret)
- goto out_mod_clk_unprepare;
+ goto out_ahb_reset_reassert;
nfc->dmac = dma_request_slave_channel(dev, "rxtx");
if (nfc->dmac) {
@@ -2247,6 +2261,9 @@
out_release_dmac:
if (nfc->dmac)
dma_release_channel(nfc->dmac);
+out_ahb_reset_reassert:
+ if (!IS_ERR(nfc->reset))
+ reset_control_assert(nfc->reset);
out_mod_clk_unprepare:
clk_disable_unprepare(nfc->mod_clk);
out_ahb_clk_unprepare:
@@ -2260,6 +2277,10 @@
struct sunxi_nfc *nfc = platform_get_drvdata(pdev);
sunxi_nand_chips_cleanup(nfc);
+
+ if (!IS_ERR(nfc->reset))
+ reset_control_assert(nfc->reset);
+
if (nfc->dmac)
dma_release_channel(nfc->dmac);
clk_disable_unprepare(nfc->mod_clk);