Re: [PATCH v2 1/3] mtd: rawnand: marvell: add suspend and resume hooks

[Boris Brezillon <boris.brezillon@bootlin.com>]

On Sat, 7 Jul 2018 08:30:25 +0200
Daniel Mack <daniel@zonque.org> wrote:

> On Saturday, July 07, 2018 08:28 AM, Daniel Mack wrote:
> > This patch restores the suspend and resume hooks that the old driver used
> > to have. Apart from stopping and starting the clocks, the resume callback
> > also nullifies the selected_chip pointer, so the next command that is issued
> > will re-select the chip and thereby restore the timing registers.
> > 
> > Without this patch, a PXA3xx based system would cough up an error similar to
> > the one below after resume.
> > 
> > [   44.660162] marvell-nfc 43100000.nand-controller: Timeout waiting for  RB signal
> > [   44.671492] ubi0 error: ubi_io_write: error -110 while writing 2048 bytes to PEB 102:38912, written 0 bytes
> > [   44.682887] CPU: 0 PID: 1417 Comm: remote-control Not tainted 4.18.0-rc2+ #344
> > [   44.691197] Hardware name: Marvell PXA3xx (Device Tree Support)
> > [   44.697111] Backtrace:
> > [   44.699593] [<c0106458>] (dump_backtrace) from [<c0106718>] (show_stack+0x18/0x1c)
> > [   44.708931]  r7:00000800 r6:00009800 r5:00000066 r4:c6139000
> > [   44.715833] [<c0106700>] (show_stack) from [<c0678a60>] (dump_stack+0x20/0x28)
> > [   44.724206] [<c0678a40>] (dump_stack) from [<c0456cbc>] (ubi_io_write+0x3d4/0x630)
> > [   44.732925] [<c04568e8>] (ubi_io_write) from [<c0454428>] (ubi_eba_write_leb+0x690/0x6fc)
> > ...
> > 
> > Signed-off-by: Daniel Mack <daniel@zonque.org>
> > Fixes: 02f26ecf8c77 ("mtd: nand: add reworked Marvell NAND controller driver")
> > Cc: stable@ivger.kernel.org  
>               ^
> 
> Ah, snap. Can you fix the typo here when applying please?

Sure, I will.

> 
> 
> Thanks,
> Daniel
> 
> 
> 
> > ---
> >   drivers/mtd/nand/raw/marvell_nand.c | 49 +++++++++++++++++++++++++++++
> >   1 file changed, 49 insertions(+)
> > 
> > diff --git a/drivers/mtd/nand/raw/marvell_nand.c b/drivers/mtd/nand/raw/marvell_nand.c
> > index 00d9f29bbdb6..4644f6e3b930 100644
> > --- a/drivers/mtd/nand/raw/marvell_nand.c
> > +++ b/drivers/mtd/nand/raw/marvell_nand.c
> > @@ -2825,6 +2825,54 @@ static int marvell_nfc_remove(struct platform_device *pdev)
> >   	return 0;
> >   }
> >   
> > +static int __maybe_unused marvell_nfc_suspend(struct device *dev)
> > +{
> > +	struct marvell_nfc *nfc = dev_get_drvdata(dev);
> > +	struct marvell_nand_chip *chip;
> > +
> > +	list_for_each_entry(chip, &nfc->chips, node)
> > +		marvell_nfc_wait_ndrun(&chip->chip);
> > +
> > +	clk_disable_unprepare(nfc->reg_clk);
> > +	clk_disable_unprepare(nfc->core_clk);
> > +
> > +	return 0;
> > +}
> > +
> > +static int __maybe_unused marvell_nfc_resume(struct device *dev)
> > +{
> > +	struct marvell_nfc *nfc = dev_get_drvdata(dev);
> > +	int ret;
> > +
> > +	ret = clk_prepare_enable(nfc->core_clk);
> > +	if (ret < 0)
> > +		return ret;
> > +
> > +	if (!IS_ERR(nfc->reg_clk)) {
> > +		ret = clk_prepare_enable(nfc->reg_clk);
> > +		if (ret < 0)
> > +			return ret;
> > +	}
> > +
> > +	/*
> > +	 * Reset nfc->selected_chip so the next command will cause the timing
> > +	 * registers to be restored in marvell_nfc_select_chip().
> > +	 */
> > +	nfc->selected_chip = NULL;
> > +
> > +	/* Reset registers that have lots its contents */
> > +	writel_relaxed(NDCR_ALL_INT | NDCR_ND_ARB_EN | NDCR_SPARE_EN |
> > +		       NDCR_RD_ID_CNT(NFCV1_READID_LEN), nfc->regs + NDCR);
> > +	writel_relaxed(0xFFFFFFFF, nfc->regs + NDSR);
> > +	writel_relaxed(0, nfc->regs + NDECCCTRL);
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct dev_pm_ops marvell_nfc_pm_ops = {
> > +	SET_SYSTEM_SLEEP_PM_OPS(marvell_nfc_suspend, marvell_nfc_resume)
> > +};
> > +
> >   static const struct marvell_nfc_caps marvell_armada_8k_nfc_caps = {
> >   	.max_cs_nb = 4,
> >   	.max_rb_nb = 2,
> > @@ -2909,6 +2957,7 @@ static struct platform_driver marvell_nfc_driver = {
> >   	.driver	= {
> >   		.name		= "marvell-nfc",
> >   		.of_match_table = marvell_nfc_of_ids,
> > +		.pm		= &marvell_nfc_pm_ops,
> >   	},
> >   	.id_table = marvell_nfc_platform_ids,
> >   	.probe = marvell_nfc_probe,
> >   
>