From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:6f8:1178:4:290:27ff:fe1d:cc33]) by canuck.infradead.org with esmtps (Exim 4.72 #1 (Red Hat Linux)) id 1PdfoR-0000aE-Ep for barebox@lists.infradead.org; Fri, 14 Jan 2011 09:19:17 +0000 Date: Fri, 14 Jan 2011 10:19:12 +0100 From: Sascha Hauer Message-ID: <20110114091912.GD24373@pengutronix.de> References: <1294963621-4177-1-git-send-email-marc@cpdesign.com.au> <1294963621-4177-3-git-send-email-marc@cpdesign.com.au> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1294963621-4177-3-git-send-email-marc@cpdesign.com.au> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH 2/2] at24: add I2C eeprom for 24cl02 To: Marc Reilly Cc: barebox@lists.infradead.org Hi Marc, On Fri, Jan 14, 2011 at 11:07:01AM +1100, Marc Reilly wrote: > This series adds a driver for at24 eeproms. Much of the guts of the code > is taken from the at24 driver in the linux kernel. > The files are located under a new misc directory, as per the kernel also. > > Signed-off-by: Marc Reilly > --- > drivers/Kconfig | 1 + > drivers/Makefile | 1 + > drivers/misc/Kconfig | 10 ++++ > drivers/misc/Makefile | 1 + > drivers/misc/at24.c | 130 +++++++++++++++++++++++++++++++++++++++++++++++++ > 5 files changed, 143 insertions(+), 0 deletions(-) > create mode 100644 drivers/misc/Kconfig > create mode 100644 drivers/misc/Makefile > create mode 100644 drivers/misc/at24.c > > diff --git a/drivers/Kconfig b/drivers/Kconfig > index 86d8fb5..c54e225 100644 > --- a/drivers/Kconfig > +++ b/drivers/Kconfig > @@ -13,5 +13,6 @@ source "drivers/mci/Kconfig" > source "drivers/clk/Kconfig" > source "drivers/mfd/Kconfig" > source "drivers/led/Kconfig" > +source "drivers/misc/Kconfig" > > endmenu > diff --git a/drivers/Makefile b/drivers/Makefile > index b1b402f..2127857 100644 > --- a/drivers/Makefile > +++ b/drivers/Makefile > @@ -11,3 +11,4 @@ obj-$(CONFIG_VIDEO) += video/ > obj-y += clk/ > obj-y += mfd/ > obj-$(CONFIG_LED) += led/ > +obj-$(CONFIG_MISC) += misc/ > diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig > new file mode 100644 > index 0000000..7da647f > --- /dev/null > +++ b/drivers/misc/Kconfig > @@ -0,0 +1,10 @@ > +menuconfig MISC > + bool "Misc devices support" > + > +if MISC > + > +config AT24 > + bool "at24 based eeprom" > + depends on I2C > + > +endif > diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile > new file mode 100644 > index 0000000..45d6553 > --- /dev/null > +++ b/drivers/misc/Makefile > @@ -0,0 +1 @@ > +obj-$(CONFIG_AT24) += at24.o > diff --git a/drivers/misc/at24.c b/drivers/misc/at24.c > new file mode 100644 > index 0000000..7bb085a > --- /dev/null > +++ b/drivers/misc/at24.c > @@ -0,0 +1,130 @@ > +/* > + * Copyright (C) 2007 Sascha Hauer, Pengutronix > + * 2009 Marc Kleine-Budde > + * 2010 Marc Reilly, Creative Product Design > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License as > + * published by the Free Software Foundation; either version 2 of > + * the License, or (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the Free Software > + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, > + * MA 02111-1307 USA > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > + > +#include > +#include > + > +#define DRIVERNAME "at24" > + > +#define to_at24(a) container_of(a, struct at24, cdev) > + > +static ssize_t at24_read(struct cdev *cdev, void *_buf, size_t count, > + ulong offset, ulong flags) > +{ > + struct at24 *priv = to_at24(cdev); > + u8 *buf = _buf; > + size_t i = count; > + ssize_t numwritten = 0; > + int retries = 5; > + int ret; > + > + while (i && retries) { > + ret = i2c_read_reg(priv->client, offset, buf, i); > + if (ret < 0) > + return (ssize_t)ret; > + else if (ret == 0) > + --retries; > + > + numwritten += ret; > + i -= ret; > + offset += ret; > + buf += ret; > + } > + > + return numwritten; > +} > + > +static ssize_t at24_write(struct cdev *cdev, const void *_buf, size_t count, > + ulong offset, ulong flags) > +{ > + struct at24 *priv = to_at24(cdev); > + const u8 *buf = _buf; > + const int maxwrite = 8; > + int numtowrite; > + ssize_t numwritten = 0; > + > + while (count) { > + int ret; > + > + numtowrite = count; > + if (numtowrite > maxwrite) > + numtowrite = maxwrite; > + > + ret = i2c_write_reg(priv->client, offset, buf, numtowrite); > + if (ret < 0) > + return (ssize_t)ret; > + > + mdelay(10); > + > + numwritten += ret; > + buf += ret; > + count -= ret; > + offset += ret; > + } > + > + return numwritten; > +} > + > +static struct file_operations at24_fops = { > + .lseek = dev_lseek_default, > + .read = at24_read, > + .write = at24_write, > +}; > + > +static int at24_probe(struct device_d *dev) > +{ > + struct at24 *at24; > + struct at24_platform_data *pdata; > + at24 = xzalloc(sizeof(*at24)); > + > + dev->priv = at24; > + pdata = dev->platform_data; > + > + at24->cdev.name = DRIVERNAME; You should use at24->cdev.name = asprintf("%s%d", DRIVERNAME, dev->id); here to support multiple eeproms. Note that this afaics needs patching i2c_new_device to initialize client->dev.id to -1 to make sure the i2c device gets an autoassigned id. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox