Re: [PATCH] Add optional chip erase functionality to AT25 EEPROM driver.

From: Greg Kroah-Hartman
Date: Fri Aug 09 2019 - 09:28:16 EST


On Fri, Aug 09, 2019 at 02:18:24PM +0100, Joe Burmeister wrote:
> Hi Greg,
>
> On 09/08/2019 14:00, Greg Kroah-Hartman wrote:
> > On Fri, Aug 09, 2019 at 01:53:55PM +0100, Joe Burmeister wrote:
> > > +static void _eeprom_at25_store_erase_locked(struct at25_data *at25)
> > > +{
> > > + unsigned long timeout, retries;
> > > + int sr, status;
> > > + u8 cp;
> > > +
> > > + cp = AT25_WREN;
> > > + status = spi_write(at25->spi, &cp, 1);
> > > + if (status < 0) {
> > > + dev_dbg(&at25->spi->dev, "ERASE WREN --> %d\n", status);
> > > + return;
> > > + }
> > > + cp = at25->erase_instr;
> > > + status = spi_write(at25->spi, &cp, 1);
> > > + if (status < 0) {
> > > + dev_dbg(&at25->spi->dev, "CHIP_ERASE --> %d\n", status);
> > > + return;
> > > + }
> > > + /* Wait for non-busy status */
> > > + timeout = jiffies + msecs_to_jiffies(ERASE_TIMEOUT);
> > > + retries = 0;
> > > + do {
> > > + sr = spi_w8r8(at25->spi, AT25_RDSR);
> > > + if (sr < 0 || (sr & AT25_SR_nRDY)) {
> > > + dev_dbg(&at25->spi->dev,
> > > + "rdsr --> %d (%02x)\n", sr, sr);
> > > + /* at HZ=100, this is sloooow */
> > > + msleep(1);
> > > + continue;
> > > + }
> > > + if (!(sr & AT25_SR_nRDY))
> > > + return;
> > > + } while (retries++ < 200 || time_before_eq(jiffies, timeout));
> > > +
> > > + if ((sr < 0) || (sr & AT25_SR_nRDY)) {
> > > + dev_err(&at25->spi->dev,
> > > + "chip erase, timeout after %u msecs\n",
> > > + jiffies_to_msecs(jiffies -
> > > + (timeout - ERASE_TIMEOUT)));
> > > + status = -ETIMEDOUT;
> > > + return;
> > > + }
> > > +}
> > > +
> > > +
> > No need for 2 lines :(
>
> Sorry, other coding conventions I'm used to.

checkpatch.pl should have warned you about this, you did run that before
sending your patch out, right?

> > > +static ssize_t eeprom_at25_store_erase(struct device *dev,
> > > + struct device_attribute *attr,
> > > + const char *buf, size_t count)
> > > +{
> > > + struct at25_data *at25 = dev_get_drvdata(dev);
> > > + int erase = 0;
> > > +
> > > + sscanf(buf, "%d", &erase);
> > > + if (erase) {
> > > + mutex_lock(&at25->lock);
> > > + _eeprom_at25_store_erase_locked(at25);
> > > + mutex_unlock(&at25->lock);
> > > + }
> > > +
> > > + return count;
> > > +}
> > > +
> > > +static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_at25_store_erase);
> > > +
> > > +
> > Same here.
> >
> > Also, where is the Documentation/ABI/ update for the new sysfs file?
>
> There isn't anything for the existing SPI EEPROM stuff I can see.
>
> Would I have to document what was already there to add my bit?

Yes, someone has to, sorry :)

thanks,

greg k-h