Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

6 files changed, 243 insertions, 0 deletions

diff --git a/Documentation/w1/masters/ds2482.rst b/Documentation/w1/masters/ds2482.rst
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+====================
+Kernel driver ds2482
+====================
+
+Supported chips:
+
+  * Maxim DS2482-100, Maxim DS2482-800
+
+    Prefix: 'ds2482'
+
+    Addresses scanned: None
+
+    Datasheets:
+
+        - http://datasheets.maxim-ic.com/en/ds/DS2482-100.pdf
+        - http://datasheets.maxim-ic.com/en/ds/DS2482-800.pdf
+
+Author: Ben Gardner <bgardner@wabtec.com>
+
+
+Description
+-----------
+
+The Maxim/Dallas Semiconductor DS2482 is a I2C device that provides
+one (DS2482-100) or eight (DS2482-800) 1-wire busses.
+
+
+General Remarks
+---------------
+
+Valid addresses are 0x18, 0x19, 0x1a, and 0x1b.
+
+However, the device cannot be detected without writing to the i2c bus, so no
+detection is done. You should instantiate the device explicitly.
+
+::
+
+  $ modprobe ds2482
+  $ echo ds2482 0x18 > /sys/bus/i2c/devices/i2c-0/new_device
diff --git a/Documentation/w1/masters/ds2490.rst b/Documentation/w1/masters/ds2490.rst
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index 000000000..842e7ae80
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+====================
+Kernel driver ds2490
+====================
+
+Supported chips:
+
+  * Maxim DS2490 based
+
+Author: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
+
+
+Description
+-----------
+
+The Maxim/Dallas Semiconductor DS2490 is a chip
+which allows to build USB <-> W1 bridges.
+
+DS9490(R) is a USB <-> W1 bus master device
+which has 0x81 family ID integrated chip and DS2490
+low-level operational chip.
+
+Notes and limitations.
+
+- The weak pullup current is a minimum of 0.9mA and maximum of 6.0mA.
+- The 5V strong pullup is supported with a minimum of 5.9mA and a
+  maximum of 30.4 mA.  (From DS2490.pdf)
+- The hardware will detect when devices are attached to the bus on the
+  next bus (reset?) operation, however only a message is printed as
+  the core w1 code doesn't make use of the information.  Connecting
+  one device tends to give multiple new device notifications.
+- The number of USB bus transactions could be reduced if w1_reset_send
+  was added to the API.  The name is just a suggestion.  It would take
+  a write buffer and a read buffer (along with sizes) as arguments.
+  The ds2490 block I/O command supports reset, write buffer, read
+  buffer, and strong pullup all in one command, instead of the current
+  1 reset bus, 2 write the match rom command and slave rom id, 3 block
+  write and read data.  The write buffer needs to have the match rom
+  command and slave rom id prepended to the front of the requested
+  write buffer, both of which are known to the driver.
+- The hardware supports normal, flexible, and overdrive bus
+  communication speeds, but only the normal is supported.
+- The registered w1_bus_master functions don't define error
+  conditions.  If a bus search is in progress and the ds2490 is
+  removed it can produce a good amount of error output before the bus
+  search finishes.
+- The hardware supports detecting some error conditions, such as
+  short, alarming presence on reset, and no presence on reset, but the
+  driver doesn't query those values.
+- The ds2490 specification doesn't cover short bulk in reads in
+  detail, but my observation is if fewer bytes are requested than are
+  available, the bulk read will return an error and the hardware will
+  clear the entire bulk in buffer.  It would be possible to read the
+  maximum buffer size to not run into this error condition, only extra
+  bytes in the buffer is a logic error in the driver.  The code should
+  match reads and writes as well as data sizes.  Reads and
+  writes are serialized and the status verifies that the chip is idle
+  (and data is available) before the read is executed, so it should
+  not happen.
+- Running x86_64 2.6.24 UHCI under qemu 0.9.0 under x86_64 2.6.22-rc6
+  with a OHCI controller, ds2490 running in the guest would operate
+  normally the first time the module was loaded after qemu attached
+  the ds2490 hardware, but if the module was unloaded, then reloaded
+  most of the time one of the bulk out or in, and usually the bulk in
+  would fail.  qemu sets a 50ms timeout and the bulk in would timeout
+  even when the status shows data available.  A bulk out write would
+  show a successful completion, but the ds2490 status register would
+  show 0 bytes written.  Detaching qemu from the ds2490 hardware and
+  reattaching would clear the problem.  usbmon output in the guest and
+  host did not explain the problem.  My guess is a bug in either qemu
+  or the host OS and more likely the host OS.
+
+03-06-2008 David Fries <David@Fries.net>
diff --git a/Documentation/w1/masters/index.rst b/Documentation/w1/masters/index.rst
new file mode 100644
index 000000000..4442a9885
--- /dev/null
+++ b/Documentation/w1/masters/index.rst
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+. SPDX-License-Identifier: GPL-2.0
+
+=====================
+1-wire Master Drivers
+=====================
+
+.. toctree::
+   :maxdepth: 1
+
+   ds2482
+   ds2490
+   mxc-w1
+   omap-hdq
+   w1-gpio
diff --git a/Documentation/w1/masters/mxc-w1.rst b/Documentation/w1/masters/mxc-w1.rst
new file mode 100644
index 000000000..334f98931
--- /dev/null
+++ b/Documentation/w1/masters/mxc-w1.rst
@@ -0,0 +1,17 @@
+====================
+Kernel driver mxc_w1
+====================
+
+Supported chips:
+
+  * Freescale MX27, MX31 and probably other i.MX SoCs
+
+    Datasheets:
+
+        - http://www.freescale.com/files/32bit/doc/data_sheet/MCIMX31.pdf?fpsp=1
+	- http://cache.freescale.com/files/dsp/doc/archive/MCIMX27.pdf?fsrch=1&WT_TYPE=Data%20Sheets&WT_VENDOR=FREESCALE&WT_FILE_FORMAT=pdf&WT_ASSET=Documentation
+
+Author:
+
+	Originally based on Freescale code, prepared for mainline by
+	Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/Documentation/w1/masters/omap-hdq.rst b/Documentation/w1/masters/omap-hdq.rst
new file mode 100644
index 000000000..5347b5d9e
--- /dev/null
+++ b/Documentation/w1/masters/omap-hdq.rst
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+========================================
+Kernel driver for omap HDQ/1-wire module
+========================================
+
+Supported chips:
+================
+HDQ/1-wire controller on the TI OMAP 2430/3430 platforms.
+
+A useful link about HDQ basics:
+===============================
+http://focus.ti.com/lit/an/slua408a/slua408a.pdf
+
+Description:
+============
+The HDQ/1-Wire module of TI OMAP2430/3430 platforms implement the hardware
+protocol of the master functions of the Benchmark HDQ and the Dallas
+Semiconductor 1-Wire protocols. These protocols use a single wire for
+communication between the master (HDQ/1-Wire controller) and the slave
+(HDQ/1-Wire external compliant device).
+
+A typical application of the HDQ/1-Wire module is the communication with battery
+monitor (gas gauge) integrated circuits.
+
+The controller supports operation in both HDQ and 1-wire mode. The essential
+difference between the HDQ and 1-wire mode is how the slave device responds to
+initialization pulse.In HDQ mode, the firmware does not require the host to
+create an initialization pulse to the slave.However, the slave can be reset by
+using an initialization pulse (also referred to as a break pulse).The slave
+does not respond with a presence pulse as it does in the 1-Wire protocol.
+
+Remarks:
+========
+The driver (drivers/w1/masters/omap_hdq.c) supports the HDQ mode of the
+controller. In this mode, as we can not read the ID which obeys the W1
+spec(family:id:crc), a module parameter can be passed to the driver which will
+be used to calculate the CRC and pass back an appropriate slave ID to the W1
+core.
+
+By default the master driver and the BQ slave i/f
+driver(drivers/w1/slaves/w1_bq27000.c) sets the ID to 1.
+Please note to load both the modules with a different ID if required, but note
+that the ID used should be same for both master and slave driver loading.
+
+e.g::
+
+  insmod omap_hdq.ko W1_ID=2
+  insmod w1_bq27000.ko F_ID=2
+
+The driver also supports 1-wire mode. In this mode, there is no need to
+pass slave ID as parameter. The driver will auto-detect slaves connected
+to the bus using SEARCH_ROM procedure. 1-wire mode can be selected by
+setting "ti,mode" property to "1w" in DT (see
+Documentation/devicetree/bindings/w1/omap-hdq.txt for more details).
+By default driver is in HDQ mode.
diff --git a/Documentation/w1/masters/w1-gpio.rst b/Documentation/w1/masters/w1-gpio.rst
new file mode 100644
index 000000000..152366055
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+++ b/Documentation/w1/masters/w1-gpio.rst
@@ -0,0 +1,47 @@
+=====================
+Kernel driver w1-gpio
+=====================
+
+Author: Ville Syrjala <syrjala@sci.fi>
+
+
+Description
+-----------
+
+GPIO 1-wire bus master driver. The driver uses the GPIO API to control the
+wire and the GPIO pin can be specified using GPIO machine descriptor tables.
+It is also possible to define the master using device tree, see
+Documentation/devicetree/bindings/w1/w1-gpio.yaml
+
+
+Example (mach-at91)
+-------------------
+
+::
+
+  #include <linux/gpio/machine.h>
+  #include <linux/w1-gpio.h>
+
+  static struct gpiod_lookup_table foo_w1_gpiod_table = {
+	.dev_id = "w1-gpio",
+	.table = {
+		GPIO_LOOKUP_IDX("at91-gpio", AT91_PIN_PB20, NULL, 0,
+			GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN),
+	},
+  };
+
+  static struct w1_gpio_platform_data foo_w1_gpio_pdata = {
+	.ext_pullup_enable_pin	= -EINVAL,
+  };
+
+  static struct platform_device foo_w1_device = {
+	.name			= "w1-gpio",
+	.id			= -1,
+	.dev.platform_data	= &foo_w1_gpio_pdata,
+  };
+
+  ...
+	at91_set_GPIO_periph(foo_w1_gpio_pdata.pin, 1);
+	at91_set_multi_drive(foo_w1_gpio_pdata.pin, 1);
+	gpiod_add_lookup_table(&foo_w1_gpiod_table);
+	platform_device_register(&foo_w1_device);