From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: Re: [PATCH v2 1/3] drivers/mfd/menf21bmc: introduce MEN 14F021P00 BMC MFD Core driver Date: Tue, 27 May 2014 16:05:47 +0100 Message-ID: <20140527150547.GA4227@lee--X1> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Andreas Werner Cc: linux-kernel@vger.kernel.org, sameo@linux.intel.com, wim@iguana.be, linux-watchdog@vger.kernel.org, cooloney@gmail.com, rpurdie@rpsys.net, linux-leds@vger.kernel.org, johannes.thumshirn@men.de List-Id: linux-leds@vger.kernel.org > The MEN 14F021P00 Board Management Controller provides an > I2C interface to the host to access the feature implemented in the BM= C. > The BMC is a PIC Microntroller assembled on CPCI Card from MEN Mikroe= lektronik > and on a few Box/Display Computer. >=20 > Added MFD Core driver, supporting the I2C communication to the device= =2E >=20 > The MFD driver currently supports the following features: > - Watchdog > - LEDs >=20 > Signed-off-by: Andreas Werner > --- > drivers/mfd/Kconfig | 12 +++ > drivers/mfd/Makefile | 1 + > drivers/mfd/menf21bmc.c | 220 ++++++++++++++++++++++++++++++++= ++++++++++ > include/linux/mfd/menf21bmc.h | 31 ++++++ > 4 files changed, 264 insertions(+) > create mode 100644 drivers/mfd/menf21bmc.c > create mode 100644 include/linux/mfd/menf21bmc.h >=20 > diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig > index ab5a43c..7c2e8d2 100644 > --- a/drivers/mfd/Kconfig > +++ b/drivers/mfd/Kconfig > @@ -427,6 +427,18 @@ config MFD_MAX8998 > additional drivers must be enabled in order to use the functional= ity > of the device. > =20 > +config MFD_MENF21BMC > + tristate "MEN 14F021P00 Board Management Controller Support" > + depends on I2C=3Dy > + select MFD_CORE > + help > + Say yes here to add support for the MEN 14F021P00 BMC > + which is a Board Management Controller connected to the I2C bus. > + This driver provides common support for accessing the devices; > + additional drivers must be enabled in order to use the > + functionality of the BMC device. Would be good if you mention the WD and LED devices here too. > + > + To many '\n's here. > config EZX_PCAP > bool "Motorola EZXPCAP Support" > depends on SPI_MASTER > diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile > index 5913208..8f2be38 100644 > --- a/drivers/mfd/Makefile > +++ b/drivers/mfd/Makefile > @@ -167,3 +167,4 @@ obj-$(CONFIG_MFD_AS3711) +=3D as3711.o > obj-$(CONFIG_MFD_AS3722) +=3D as3722.o > obj-$(CONFIG_MFD_STW481X) +=3D stw481x.o > obj-$(CONFIG_MFD_IPAQ_MICRO) +=3D ipaq-micro.o > +obj-$(CONFIG_MFD_MENF21BMC) +=3D menf21bmc.o > diff --git a/drivers/mfd/menf21bmc.c b/drivers/mfd/menf21bmc.c > new file mode 100644 > index 0000000..8de92b5 > --- /dev/null > +++ b/drivers/mfd/menf21bmc.c > @@ -0,0 +1,220 @@ > +/* > + * MEN 14F021P00 Board Management Controller (BMC) MFD Core Driver. > + * > + * Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH > + * Author: Andreas Werner > + * All rights reserved. > + * > + * This program is free software; you can redistribute it and/or m= odify it > + * under the terms of the GNU General Public License as publishe= d by the > + * Free Software Foundation; either version 2 of the License, or = (at your > + * option) any later version. > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define BMC_CMD_REV_MAJOR 0x80 > +#define BMC_CMD_REV_MINOR 0x81 > +#define BMC_CMD_REV_MAIN 0x82 > +#define BMC_CMD_REV_BUILD 0x83 > +#define BMC_CMD_REV_VERI 0x84 > +#define BMC_CMD_WD_ARM_SET 0x18 > +#define BMC_CMD_WD_ARM_GET 0x19 > + > +static struct mfd_cell menf21bmc_cell[] =3D { > + { > + .name =3D "menf21bmc_wd", I prefer wdog to wd, as it's a little move obvious what we're dealing with. > + }, > + { > + .name =3D "menf21bmc_led", > + }, > +}; If these are the only struct attributes, please place them on a single line (each). > +static int > +menf21bmc_read_byte_data(struct i2c_client *client, u8 reg) > +{ > + int ret; > + struct menf21bmc *data =3D i2c_get_clientdata(client); > + > + mutex_lock(&data->lock); > + ret =3D i2c_smbus_read_byte_data(client, reg); > + mutex_unlock(&data->lock); > + > + return ret; > +} > + > +static int > +menf21bmc_read_word_data(struct i2c_client *client, u8 reg) > +{ > + int ret; > + struct menf21bmc *data =3D i2c_get_clientdata(client); > + > + mutex_lock(&data->lock); > + ret =3D i2c_smbus_read_word_data(client, reg); > + mutex_unlock(&data->lock); > + > + return ret; > +} > + > +static int menf21bmc_write_byte_data(struct i2c_client *client, u8 r= eg, u8 val) > +{ > + int ret; > + struct menf21bmc *data =3D i2c_get_clientdata(client); > + > + mutex_lock(&data->lock); > + ret =3D i2c_smbus_write_byte_data(client, reg, val); > + mutex_unlock(&data->lock); > + > + return ret; > +} > + > +static int menf21bmc_write_word_data(struct i2c_client *client, u8 r= eg, u16 val) > +{ > + int ret; > + struct menf21bmc *data =3D i2c_get_clientdata(client); > + > + mutex_lock(&data->lock); > + ret =3D i2c_smbus_write_word_data(client, reg, val); > + mutex_unlock(&data->lock); > + > + return ret; > +} > + > +static int menf21bmc_write_byte(struct i2c_client *client, u8 val) > +{ > + int ret; > + struct menf21bmc *data =3D i2c_get_clientdata(client); > + > + mutex_lock(&data->lock); > + ret =3D i2c_smbus_write_byte(client, val); > + mutex_unlock(&data->lock); > + > + return ret; > +} Didn't we ask you to remove these? Just make the i2c_smbus_* calls from within the driver. The I2C subsystem conducts its own locking. I'm really starting to frown on aggregation for the sake of aggregation. It's just overhead. > +static int menf21bmc_wd_leave_prod_mode(struct i2c_client *client) > +{ > + int val, ret; > + > + val =3D menf21bmc_read_byte_data(client, BMC_CMD_WD_ARM_GET); ARM like the processor, or 'arm' as in "arm the missile", or something else? > + if (val < 0) > + return val; > + > + /* > + * Production mode should be not active after delivery of the Board= =2E > + * To be sure we check it, inform the user and leave the mode > + * if active. > + */ I prefer the term 'exit', as 'leave' is ambiguous. It could read "leave it in production mode", or "leave (exit) production mode". > + if (val =3D=3D 0x00) { > + dev_info(&client->dev, > + "BMC in production mode. Leave production mode\n"); > + > + ret =3D menf21bmc_write_byte(client, BMC_CMD_WD_ARM_SET); > + if (ret < 0) > + return ret; > + } > + > + return 0; > +} > + > +static int > +menf21bmc_probe(struct i2c_client *client, const struct i2c_device_i= d *ids) > +{ > + int ret; > + struct menf21bmc *data; > + int rev_major, rev_minor, rev_main; > + > + if (!i2c_check_functionality(client->adapter, > + I2C_FUNC_SMBUS_BYTE_DATA | > + I2C_FUNC_SMBUS_WORD_DATA | > + I2C_FUNC_SMBUS_BYTE)) Tabbing is off. Try to line up with the '('. > + return -EIO; -ENODEV is more common. > + data =3D devm_kzalloc(&client->dev, sizeof(struct menf21bmc), GFP_K= ERNEL); s/sizeof(struct menf21bmc)/sizeof(*data)/ data doesn't tend to be a good name for a variable. > + if (data =3D=3D NULL) if (!data) > + return -ENOMEM; > + > + mutex_init(&data->lock); > + > + i2c_set_clientdata(client, data); > + data->client =3D client; > + data->read_word_data =3D menf21bmc_read_word_data; > + data->read_byte_data =3D menf21bmc_read_byte_data; > + data->write_word_data =3D menf21bmc_write_word_data; > + data->write_byte_data =3D menf21bmc_write_byte_data; > + data->write_byte =3D menf21bmc_write_byte; Yuck, please remove these. > + rev_major =3D menf21bmc_read_word_data(client, BMC_CMD_REV_MAJOR); > + if (rev_major < 0) { > + dev_err(&client->dev, "failed to get BMC major revision\n"); > + return rev_major; > + } > + > + rev_minor =3D menf21bmc_read_word_data(client, BMC_CMD_REV_MINOR); > + if (rev_minor < 0) { > + dev_err(&client->dev, "failed to get BMC minor revision\n"); > + return rev_minor; > + } > + > + rev_main =3D menf21bmc_read_word_data(client, BMC_CMD_REV_MAIN); > + if (rev_main < 0) { > + dev_err(&client->dev, "failed to get BMC main revision\n"); > + return rev_main; > + } > + > + dev_info(&client->dev, "FW Revision: %02d.%02d.%02d\n", > + rev_major, rev_minor, rev_main); > + > + /* > + * We have to leave the Production Mode of the BMC to activate the > + * Watchdog functionality and the BIOS life sign monitoring. > + */ > + ret =3D menf21bmc_wd_leave_prod_mode(client); > + if (ret < 0) { > + dev_err(&client->dev, "failed to leave production mode\n"); > + return ret; > + } Is it possible that someone might want to use production mode? > + ret =3D mfd_add_devices(&client->dev, 0, menf21bmc_cell, > + ARRAY_SIZE(menf21bmc_cell), NULL, 0, NULL); > + if (ret < 0) { > + dev_err(&client->dev, "mfd_add_devices failed\n"); This error message should be more useful to the user. E.g. "Failed to add sub-devices" > + return ret; > + } > + > + return 0; > +} > + > +static int menf21bmc_remove(struct i2c_client *client) > +{ > + mfd_remove_devices(&client->dev); > + return 0; > +} > + > +static const struct i2c_device_id menf21bmc_id_table[] =3D { > + {"menf21bmc", 0}, Please add a ' ' after '{' and before '}'. > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, menf21bmc_id_table); > + > +static struct i2c_driver menf21bmc_driver =3D { > + .driver =3D { > + .name =3D "menf21bmc", > + .owner =3D THIS_MODULE, > + }, > + .id_table =3D menf21bmc_id_table, > + .probe =3D menf21bmc_probe, > + .remove =3D menf21bmc_remove, > +}; > + > +module_i2c_driver(menf21bmc_driver); > + > +MODULE_DESCRIPTION("MEN 14F021P00 BMC mfd core driver"); > +MODULE_AUTHOR("Andreas Werner '. > +MODULE_LICENSE("GPL"); > diff --git a/include/linux/mfd/menf21bmc.h b/include/linux/mfd/menf21= bmc.h > new file mode 100644 > index 0000000..1fc9b5c > --- /dev/null > +++ b/include/linux/mfd/menf21bmc.h > @@ -0,0 +1,31 @@ > +/* > + * MEN 14F021P00 Board Management Controller (BMC) > + * > + * Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH > + * Author: Andreas Werner > + * All rights reserved. > + * > + * This program is free software; you can redistribute it and/or m= odify it > + * under the terms of the GNU General Public License as publishe= d by the > + * Free Software Foundation; either version 2 of the License, or = (at your > + * option) any later version. > + * > + */ > + > +#ifndef MENF21BMC_H > +#define MENF21BMC_H > + > +struct menf21bmc { > + struct i2c_client *client; > + struct mutex lock; > + > + int (*read_word_data)(struct i2c_client *client, u8 reg); > + int (*read_byte_data)(struct i2c_client *client, u8 reg); > + int (*write_word_data)(struct i2c_client *client, u8 reg, u16 val); > + int (*write_byte_data)(struct i2c_client *client, u8 reg, u8 val); > + int (*write_byte)(struct i2c_client *client, u8 val); > +}; > + > +#endif /* MENF21BMC_H */ > + > + Too many '\n's here. --=20 Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org =E2=94=82 Open source software for ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog