On Mon, 19 May 2014, Guenter Roeck wrote: > On 05/19/2014 05:43 AM, Andreas Werner wrote: > >aOn Sat, May 17, 2014 at 08:47:42AM -0700, Guenter Roeck wrote: > >>On 05/16/2014 09:37 AM, Andreas Werner wrote: > >>>The MEN 14F021P00 Board Management Controller provides an > >>>I2C interface to the host to access the feature implemented in the BMC. > >>>The BMC is a PIC Microntroller assembled on CPCI Card from MEN > >>>Mikroelektronik > >>>and on a few Box/Display Computer. > >>> > >>>Added MFD Core driver, supporting the I2C communication to the device. > >>> > >>>The MFD driver currently supports the following features: > >>> - Watchdog > >>> - LEDs > >>> > >>>Signed-off-by: Andreas Werner <[email protected]> > >>>--- > >>> drivers/mfd/Kconfig | 12 +++ > >>> drivers/mfd/Makefile | 1 + > >>> drivers/mfd/menf21bmc.c | 193 > >>> ++++++++++++++++++++++++++++++++++++++++++ > >>> include/linux/mfd/menf21bmc.h | 32 +++++++ > >>> 4 files changed, 238 insertions(+) > >>> create mode 100644 drivers/mfd/menf21bmc.c > >>> create mode 100644 include/linux/mfd/menf21bmc.h > >>> > >>>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 functionality > >>> of the device. > >>> > >>>+config MFD_MENF21BMC > >>>+ tristate "MEN 14F021P00 Board Management Controller Support" > >>>+ depends on I2C=y > >>>+ 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. > >>>+ > >>>+ > >>> 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-$(CONFIG_MFD_AS3711) += as3711.o > >>> obj-$(CONFIG_MFD_AS3722) += as3722.o > >>> obj-$(CONFIG_MFD_STW481X) += stw481x.o > >>> obj-$(CONFIG_MFD_IPAQ_MICRO) += ipaq-micro.o > >>>+obj-$(CONFIG_MFD_MENF21BMC) += menf21bmc.o > >>>diff --git a/drivers/mfd/menf21bmc.c b/drivers/mfd/menf21bmc.c > >>>new file mode 100644 > >>>index 0000000..77de1a8 > >>>--- /dev/null > >>>+++ b/drivers/mfd/menf21bmc.c > >>>@@ -0,0 +1,193 @@ > >>>+/* > >>>+ * MEN 14F021P00 Board Management Controller (BMC) MFD Core Driver. > >>>+ * > >>>+ * Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH > >>>+ * Author: Andreas Werner <[email protected]> > >>>+ * All rights reserved. > >>>+ * > >>>+ * 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. > >>>+ * > >>>+ */ > >>>+ > >>>+#include <linux/kernel.h> > >>>+#include <linux/device.h> > >>>+#include <linux/module.h> > >>>+#include <linux/i2c.h> > >>>+#include <linux/mfd/core.h> > >>>+#include <linux/mfd/menf21bmc.h> > >>>+ > >>>+#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 > >>>+ > >>>+static struct mfd_cell menf21bmc_cell[] = { > >>>+ { > >>>+ .name = "menf21bmc_wd", > >>>+ }, > >>>+ { > >>>+ .name = "menf21bmc_led", > >>>+ }, > >>>+}; > >>>+ > >>>+static int > >>>+menf21bmc_read_byte_data(struct i2c_client *client, u8 reg, uint8_t *val) > >>>+{ > >>>+ int ret; > >>>+ struct menf21bmc *data = i2c_get_clientdata(client); > >>>+ > >>>+ mutex_lock(&data->lock); > >>>+ ret = i2c_smbus_read_byte_data(client, reg); > >>>+ mutex_unlock(&data->lock); > >>>+ > >>>+ if (ret < 0) { > >>>+ dev_err(&client->dev, "failed to read byte at 0x%02x\n", reg); > >>>+ return ret; > >>>+ } > >>>+ > >>>+ *val = (uint8_t)ret; > >>>+ > >>>+ return 0; > >>>+} > >>>+ > >>I personally would prefer if you would retain the original API, which > >>returns both value > >>and error code as return value. I don't see the benefit of changing the API > >>as you did - > >>it just complicates the code. > >> > >>Thanks, > >>Guenter > >> > >I think it is ok for a wrapper like this because it does not really change > >an API because > >it is menf21bmc related. > > > >I did the same in rtc-rx8581, and it was already done in rtc_ds1307.c. > > > >I personally prefer this way because the return of the function and the > >return > >value of the i2c_smbus_read - which is the value read from the device - are > >seperated. > > > >If it is a no go for the mfd/wdt core i can change it back to the original > >i2c_smbus API. > >If it is ok on your side for a wrapper like this, we can let it as it is. > > > > Not my call to make; depends on the mfd maintainer. I would not accept it, as > I see it > as unnecessary, adding complexity, and pointless. Sure, you can always find > examples > for everything somewhere in the kernel, but that doesn't make it better.
I'm inclined to agree with Guenter, this patch is just noise. -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
