Re: [patch v3 1/2] mfd: Add Mellanox regmap core driver

On Thu, Aug 03, 2017 at 12:02:12PM +0000, Vadim Pasternak wrote:

This patch adds core regmap platform driver for Mellanox BMC cards with
the programmable devcies based chassis control. The device logics,
controlled by software includes:
- Interrupt handling for chassis, ASIC, CPU events;
- LED handling;
- Exposes through sysfs mux, reset signals, reset cause notification;
The patch provides support for the access to programmable device through
the register map and allows dynamic device tree manipulation at runtime
for removable devices.

This driver requires activator driver, which responsibility is to create
register map and pass it to regmap core. Such activator could be based for
example on I2C, SPI or  MMIO interface.

Drivers exposes the number of hwmon attributes to sysfs according to the
attribute groups, defined in the device tree. These attributes will be
located for example in /sys/class/hwmon/hwmonX folder, which is a symbolic
link to for example:
/sys/bus/i2c/devices/4-0072/mlxreg-core.1138/hwmon/hwmon10.
The attributes are divided to the groups, like in the below example:
 MUX nodes
 - safe_bios_disable
 - spi_burn_bios_ci
 - spi_burn_ncsi
 - uart_sel
 Reset nodes:
 - sys_power_cycle
 - bmc_upgrade
 - asic_reset
 Cause of reset nodes:
 - cpu_kernel_panic
 - cpu_shutdown
 - bmc_warm_reset
 PSU nodes' statuses
 - psu1
 - psu2
 FAN nodes' statuses:
 - fan1
 - fan2
 Power cable nodes' statuses:
 - pwr1
 - pwr2
 Asic nodes' statuses:
 - asic1
 - asic2
 General purpose RW nodes:
 - version

Drivers also probes LED platform driver, in case device tree description
contains LED nodes.

Signed-off-by: Vadim Pasternak <redacted>
---
v2->v3:
 Changes added by Vadim:
 - Change name of field led data in struct mlxreg_core_led_platform_data
   in mlxreg.h;
 - fix data position assignment in mlxreg_core_get;
 - update name of field led data in mlxreg_core_set_led;
v1->v2:
 Comments pointed out by Pavel:
 - Remove extra new line in mellanox,mlxreg-core;
 - Replace three NOT with one in mlxreg_core_attr_show;
 - Make error message in mlxreg_core_work_helper shorter;
 - Make attribute assignment more readable;
 - Separate mellanox,mlxreg-core file for sending to DT mainataners.
 Comments pointed out by Jacek:
 - Since  brightness_set_blocking is used instead of
   brightness_set, three fields from mlxreg_core_led_data.
---
 .../devicetree/bindings/vendor-prefixes.txt        |    1 +

Please make this a separate patch.

 MAINTAINERS                                        |    7 +
 drivers/mfd/Kconfig                                |   15 +
 drivers/mfd/Makefile                               |    1 +
 drivers/mfd/mlxreg-core.c                          | 1263 ++++++++++++++++++++
 include/linux/platform_data/mlxreg.h               |   87 ++
 6 files changed, 1374 insertions(+)
 create mode 100644 drivers/mfd/mlxreg-core.c
 create mode 100644 include/linux/platform_data/mlxreg.h

The binding should be part of this series. And add a ".txt" to this 
file.

+F:	drivers/mfd/mlxreg-core.c
+F:	include/linux/platform_data/mlxreg.h
+
 MELLANOX ETHERNET DRIVER (mlx4_en)
 M:	Tariq Toukan [off-list ref]
 L:	netdev@vger.kernel.org