[PATCH v7 2/2] mtd: nand: sunxi: add reset line support
From: Icenowy Zheng <hidden>
Date: 2016-06-24 05:00:05
Also in:
linux-arm-kernel
Subsystem:
memory technology devices (mtd), nand flash subsystem, the rest · Maintainers:
Miquel Raynal, Richard Weinberger, Vignesh Raghavendra, Linus Torvalds
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 <redacted>
---
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.
Changes in v6:
- Fixed a resource leak by not using goto to exit in case of error.
Changes in v7:
- Rebased for nand/next branch.
drivers/mtd/nand/sunxi_nand.c | 26 ++++++++++++++++++++++++--
1 file changed, 24 insertions(+), 2 deletions(-)
diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index f582fe4..77796da 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 @@ 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;
@@ -2209,15 +2211,28 @@ 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) { + 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 +2262,9 @@ static int sunxi_nfc_probe(struct platform_device *pdev) 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:
@@ -2262,6 +2280,10 @@ static int sunxi_nfc_remove(struct platform_device *pdev) sunxi_nand_chips_cleanup(nfc); if (nfc->dmac) dma_release_channel(nfc->dmac); + + if (!IS_ERR(nfc->reset)) + reset_control_assert(nfc->reset); + clk_disable_unprepare(nfc->mod_clk); clk_disable_unprepare(nfc->ahb_clk);
--
2.9.0