On Thu, Mar 14, 2013 at 03:06:59PM +0100, Jon Arne Jørgensen wrote: > This file is responsible for registering the device > with the kernel i2c subsystem. > v4l2 talks to the saa7113 chip of the device via i2c. > > Signed-off-by: Jon Arne Jørgensen <jonarne@xxxxxxxxxx> > --- > drivers/media/usb/smi2021/smi2021_i2c.c | 160 ++++++++++++++++++++++++++++++++ > 1 file changed, 160 insertions(+) > create mode 100644 drivers/media/usb/smi2021/smi2021_i2c.c > > diff --git a/drivers/media/usb/smi2021/smi2021_i2c.c b/drivers/media/usb/smi2021/smi2021_i2c.c > new file mode 100644 > index 0000000..5b6f3f5 > --- /dev/null > +++ b/drivers/media/usb/smi2021/smi2021_i2c.c > @@ -0,0 +1,160 @@ > +/******************************************************************************* > + * smi2021_i2c.c * > + * * > + * USB Driver for SMI2021 - EasyCAP * > + * USB ID 1c88:003c * > + * * > + * ***************************************************************************** > + * > + * Copyright 2011-2013 Jon Arne Jørgensen > + * <jonjon.arnearne--a.t--gmail.com> > + * > + * Copyright 2011, 2012 Tony Brown, Michal Demin, Jeffry Johnston > + * > + * This file is part of SMI2021 > + * http://code.google.com/p/easycap-somagic-linux/ > + * > + * 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, see <http://www.gnu.org/licenses/>. > + * > + * This driver is heavily influensed by the STK1160 driver. > + * Copyright (C) 2012 Ezequiel Garcia > + * <elezegarcia--a.t--gmail.com> > + * > + */ > + > +#include "smi2021.h" > + > +/* The device will not return the chip_name on address 0x00. > + * But the saa7115 i2c driver needs the chip id to match "f7113" > + * if we want to use it, > + * so we have to fake the return of this value > + */ This comment style is wrong, check Documentation/CodingStyle. BTW, Did you check the patches with checkpatch.pl? (you can add checkpatch.pl as a git pre-commit hook, which I find very useful) > + > +static char chip_id[] = { 'x', 255, 55, 49, 49, 115, 0 }; > +static int id_ptr; > + > +static unsigned int i2c_debug; > +module_param(i2c_debug, int, 0644); > +MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]"); > + > +#define dprint_i2c(fmt, args...) \ > +do { \ > + if (i2c_debug) \ > + pr_debug("smi2021[i2c]::%s: " fmt, __func__, ##args); \ > +} while (0) > + > + > +static int i2c_xfer(struct i2c_adapter *i2c_adap, > + struct i2c_msg msgs[], int num) > +{ > + struct smi2021_dev *dev = i2c_adap->algo_data; > + > + switch (num) { > + case 2: { /* Read reg */ Do you need a local scope in here? > + if (msgs[0].len != 1 || msgs[1].len != 1) { > + dprint_i2c("both messages must be 1 byte\n"); > + goto err_out; > + I think you missed a closing } here. And an opening { below... > + if ((msgs[1].flags & I2C_M_RD) != I2C_M_RD) > + dprint_i2c("last message should have rd flag\n"); > + goto err_out; > + } > + > + if (msgs[0].buf[0] == 0) { > + msgs[1].buf[0] = chip_id[id_ptr]; > + if (chip_id[id_ptr] != 0) > + id_ptr += 1; > + } else { > + smi2021_read_reg(dev, msgs[0].addr, msgs[0].buf[0], > + msgs[1].buf); > + } > + break; > + } > + case 1: { /* Write reg */ > + if (msgs[0].len == 0) { > + break; > + } else if (msgs[0].len != 2) { > + dprint_i2c("unsupported len\n"); > + goto err_out; > + } > + if (msgs[0].buf[0] == 0) { > + /* We don't handle writing to addr 0x00 */ > + break; > + } > + > + smi2021_write_reg(dev, msgs[0].addr, msgs[0].buf[0], > + msgs[0].buf[1]); > + break; > + } > + default: { > + dprint_i2c("driver can only handle 1 or 2 messages\n"); > + goto err_out; > + } > + } > + return num; > + > +err_out: > + return -EOPNOTSUPP; > +} > + > +static u32 functionality(struct i2c_adapter *adap) > +{ > + return I2C_FUNC_SMBUS_EMUL; > +} > + > +static struct i2c_algorithm algo = { > + .master_xfer = i2c_xfer, > + .functionality = functionality, > +}; > + > +static struct i2c_adapter adap_template = { > + .owner = THIS_MODULE, > + .name = "smi2021_easycap_dc60", > + .algo = &algo, > +}; > + > +static struct i2c_client client_template = { > + .name = "smi2021 internal", > +}; > + > +int smi2021_i2c_register(struct smi2021_dev *dev) > +{ > + int rc; > + > + id_ptr = 0; You don't need to initialize id_ptr here. > + > + dev->i2c_adap = adap_template; > + dev->i2c_adap.dev.parent = dev->dev; > + strcpy(dev->i2c_adap.name, "smi2021"); > + dev->i2c_adap.algo_data = dev; > + > + i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev); > + > + rc = i2c_add_adapter(&dev->i2c_adap); > + if (rc < 0) { > + smi2021_err("can't add i2c adapter, errno: %d\n", rc); > + return rc; > + } > + > + dev->i2c_client = client_template; > + dev->i2c_client.adapter = &dev->i2c_adap; > + > + return 0; > +} > + > +int smi2021_i2c_unregister(struct smi2021_dev *dev) > +{ > + i2c_del_adapter(&dev->i2c_adap); > + return 0; > +} > -- > 1.8.1.1 > -- Ezequiel García, Free Electrons Embedded Linux, Kernel and Android Engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
