| Message ID | 20160620044838.56904-2-icenowy@aosc.xyz |
|---|---|
| State | New |
| Headers | show |
On Mon, Jun 20, 2016 at 12:48:38PM +0800, Icenowy Zheng wrote: > 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> Thanks, Maxime
On Mon, 20 Jun 2016 12:48:38 +0800 Icenowy Zheng <icenowy@aosc.xyz> wrote: > 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> > --- > 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. > > drivers/mtd/nand/sunxi_nand.c | 28 +++++++++++++++++++++++++--- > 1 file changed, 25 insertions(+), 3 deletions(-) > > diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c > index a83a690..08d5e88 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 +1873,42 @@ 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); You should return -EDEFER_PROBE here. And can you please rebase this series on top of nand/next [1]? [1]https://github.com/linux-nand/linux/tree/nand/next
In my opinion, return directly PTR_ERR(nfc->reset) is OK here. If devm_reset_control_get_optional() return -EPROBE_DEFER, the code here will also return it. However, if we get other error, why should it return -EPROBE_DEFER again? 24.06.2016, 00:01, "Boris Brezillon" <boris.brezillon@free-electrons.com>: > On Mon, 20 Jun 2016 12:48:38 +0800 > Icenowy Zheng <icenowy@aosc.xyz> wrote: > >> 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> >> --- >> 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. >> >> drivers/mtd/nand/sunxi_nand.c | 28 +++++++++++++++++++++++++--- >> 1 file changed, 25 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c >> index a83a690..08d5e88 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 +1873,42 @@ 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); > > You should return -EDEFER_PROBE here. > > And can you please rebase this series on top of nand/next [1]? > > [1]https://github.com/linux-nand/linux/tree/nand/next
On Fri, 24 Jun 2016 07:20:38 +0800 Icenowy Zheng <icenowy@aosc.xyz> wrote: > In my opinion, return directly PTR_ERR(nfc->reset) is OK here. > If devm_reset_control_get_optional() return -EPROBE_DEFER, the code here will also return it. However, if we get other error, why should it return -EPROBE_DEFER again? Sorry, I just had a brainfart :-). Your implementation is correct. BTW, can you avoid top-posting and reply inline? > > 24.06.2016, 00:01, "Boris Brezillon" <boris.brezillon@free-electrons.com>: > > On Mon, 20 Jun 2016 12:48:38 +0800 > > Icenowy Zheng <icenowy@aosc.xyz> wrote: > > > >> 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> > >> --- > >> 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. > >> > >> drivers/mtd/nand/sunxi_nand.c | 28 +++++++++++++++++++++++++--- > >> 1 file changed, 25 insertions(+), 3 deletions(-) > >> > >> diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c > >> index a83a690..08d5e88 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 +1873,42 @@ 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); > > > > You should return -EDEFER_PROBE here. > > > > And can you please rebase this series on top of nand/next [1]? > > > > [1]https://github.com/linux-nand/linux/tree/nand/next
diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c index a83a690..08d5e88 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 +1873,42 @@ 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; platform_set_drvdata(pdev, nfc); ret = sunxi_nand_chips_init(dev, nfc); if (ret) { dev_err(dev, "failed to init nand chips\n"); - goto out_mod_clk_unprepare; + goto out_ahb_reset_reassert; } return 0; +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: @@ -1904,6 +1922,10 @@ static int sunxi_nfc_remove(struct platform_device *pdev) struct sunxi_nfc *nfc = platform_get_drvdata(pdev); sunxi_nand_chips_cleanup(nfc); + + if (!IS_ERR(nfc->reset)) + reset_control_assert(nfc->reset); + clk_disable_unprepare(nfc->mod_clk); clk_disable_unprepare(nfc->ahb_clk);
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> --- 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. drivers/mtd/nand/sunxi_nand.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-)