Commit Graph

28 Commits

Author SHA1 Message Date
Jae Hyun Yoo
7604978e85 Revert "i3c master: fix missing destroy_workqueue() on error in i3c_master_register"
commit 0d95f41ebde40d552bb4fea64b1d618607915fd6 upstream.

Adding the destroy_workqueue call in i3c_master_register introduced below
kernel warning because it makes duplicate destroy_workqueue calls when
i3c_master_register fails after allocating the workqueue. The workqueue will
be destroyed by i3c_masterdev_release which is called by put_device at the
end of the i3c_master_register function eventually in failure cases so the
workqueue doesn't need to be destroyed in i3c_master_register.

[    6.972952] WARNING: CPU: 1 PID: 1 at lib/list_debug.c:48 __list_del_entry_valid+0x9c/0xf4
[    6.982205] list_del corruption, 8fe03c08->prev is LIST_POISON2 (00000122)
[    6.989910] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G        W         5.10.23-c12838a-dirty-31dc772 #1
[    7.000295] Hardware name: Generic DT based system
[    7.005638] Backtrace:
[    7.008369] [<809133f0>] (dump_backtrace) from [<80913644>] (show_stack+0x20/0x24)
[    7.016819]  r7:00000030 r6:60000013 r5:00000000 r4:813b5d40
[    7.023137] [<80913624>] (show_stack) from [<8091e1a0>] (dump_stack+0x9c/0xb0)
[    7.031201] [<8091e104>] (dump_stack) from [<8011fa30>] (__warn+0xf8/0x154)
[    7.038972]  r7:00000030 r6:00000009 r5:804fa1c8 r4:80b6eca4
[    7.045289] [<8011f938>] (__warn) from [<80913d14>] (warn_slowpath_fmt+0x8c/0xc0)
[    7.053641]  r7:00000030 r6:80b6eca4 r5:80b6ed74 r4:818cc000
[    7.059960] [<80913c8c>] (warn_slowpath_fmt) from [<804fa1c8>] (__list_del_entry_valid+0x9c/0xf4)
[    7.069866]  r9:96becf8c r8:818cc000 r7:8fe03c10 r6:8fe03c00 r5:8fe03ba0 r4:ff7ead4c
[    7.078513] [<804fa12c>] (__list_del_entry_valid) from [<8013f0b4>] (destroy_workqueue+0x1c4/0x23c)
[    7.088615] [<8013eef0>] (destroy_workqueue) from [<806aa124>] (i3c_masterdev_release+0x40/0xb0)
[    7.098421]  r7:00000000 r6:81a43b80 r5:8fe65360 r4:8fe65048
[    7.104740] [<806aa0e4>] (i3c_masterdev_release) from [<805f3f04>] (device_release+0x40/0xb0)
[    7.114254]  r5:00000000 r4:8fe65048
[    7.118245] [<805f3ec4>] (device_release) from [<808fe754>] (kobject_put+0xc8/0x204)
[    7.126885]  r5:813978dc r4:8fe65048
[    7.130877] [<808fe68c>] (kobject_put) from [<805f5fbc>] (put_device+0x20/0x24)
[    7.139037]  r7:8fe65358 r6:8fe65368 r5:8fe65358 r4:8fe65048
[    7.145355] [<805f5f9c>] (put_device) from [<806abac4>] (i3c_master_register+0x338/0xb00)
[    7.154487] [<806ab78c>] (i3c_master_register) from [<806ae084>] (dw_i3c_probe+0x224/0x24c)
[    7.163811]  r10:00000000 r9:8fe7a100 r8:00000032 r7:819fa810 r6:819fa800 r5:8fe65040
[    7.172547]  r4:00000000
[    7.175376] [<806ade60>] (dw_i3c_probe) from [<805fdc14>] (platform_drv_probe+0x44/0x80)
[    7.184409]  r9:813a25c0 r8:00000000 r7:815ec114 r6:00000000 r5:813a25c0 r4:819fa810
[    7.193053] [<805fdbd0>] (platform_drv_probe) from [<805fb83c>] (really_probe+0x108/0x50c)
[    7.202275]  r5:815ec004 r4:819fa810
[    7.206265] [<805fb734>] (really_probe) from [<805fc180>] (driver_probe_device+0xb4/0x190)
[    7.215492]  r10:813dc000 r9:80c4385c r8:000000d9 r7:813a25c0 r6:819fa810 r5:00000000
[    7.224228]  r4:813a25c0
[    7.227055] [<805fc0cc>] (driver_probe_device) from [<805fc5cc>] (device_driver_attach+0xb8/0xc0)
[    7.236959]  r9:80c4385c r8:000000d9 r7:813a25c0 r6:819fa854 r4:819fa810
[    7.244439] [<805fc514>] (device_driver_attach) from [<805fc65c>] (__driver_attach+0x88/0x16c)
[    7.254051]  r7:00000000 r6:819fa810 r5:00000000 r4:813a25c0
[    7.260369] [<805fc5d4>] (__driver_attach) from [<805f954c>] (bus_for_each_dev+0x88/0xc8)
[    7.269489]  r7:00000000 r6:818cc000 r5:805fc5d4 r4:813a25c0
[    7.275806] [<805f94c4>] (bus_for_each_dev) from [<805fc76c>] (driver_attach+0x2c/0x30)
[    7.284739]  r7:81397c98 r6:00000000 r5:8fe7db80 r4:813a25c0
[    7.291057] [<805fc740>] (driver_attach) from [<805f9eec>] (bus_add_driver+0x120/0x200)
[    7.299984] [<805f9dcc>] (bus_add_driver) from [<805fce44>] (driver_register+0x98/0x128)
[    7.309005]  r7:80c4383c r6:00000000 r5:00000000 r4:813a25c0
[    7.315323] [<805fcdac>] (driver_register) from [<805fedb4>] (__platform_driver_register+0x50/0x58)
[    7.325410]  r5:818cc000 r4:81397c98
[    7.329404] [<805fed64>] (__platform_driver_register) from [<80c23398>] (dw_i3c_driver_init+0x24/0x28)
[    7.339790]  r5:818cc000 r4:80c23374
[    7.343784] [<80c23374>] (dw_i3c_driver_init) from [<80c01300>] (do_one_initcall+0xac/0x1d0)
[    7.353206] [<80c01254>] (do_one_initcall) from [<80c01630>] (kernel_init_freeable+0x1a8/0x204)
[    7.362916]  r8:000000d9 r7:80c4383c r6:00000007 r5:819ca2c0 r4:80c67680
[    7.370398] [<80c01488>] (kernel_init_freeable) from [<8091eb18>] (kernel_init+0x18/0x12c)
[    7.379616]  r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:8091eb00
[    7.388343]  r4:00000000
[    7.391170] [<8091eb00>] (kernel_init) from [<80100148>] (ret_from_fork+0x14/0x2c)
[    7.399607] Exception stack(0x818cdfb0 to 0x818cdff8)
[    7.405243] dfa0:                                     00000000 00000000 00000000 00000000
[    7.414371] dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    7.423499] dfe0: 00000000 00000000 00000000 00000000 00000013 00000000
[    7.430879]  r5:8091eb00 r4:00000000

This reverts commit 59165d16c699182b86b5c65181013f1fd88feb62.

Fixes: 59165d16c699 ("i3c master: fix missing destroy_workqueue() on error in i3c_master_register")
Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210408172803.24599-1-jae.hyun.yoo@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14 09:50:05 +02:00
Qinglang Miao
06ac2ca098 i3c master: fix missing destroy_workqueue() on error in i3c_master_register
[ Upstream commit 59165d16c699182b86b5c65181013f1fd88feb62 ]

Add the missing destroy_workqueue() before return from
i3c_master_register in the error handling case.

Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-i3c/20201028091543.136167-1-miaoqinglang@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-06 14:56:53 +01:00
Parshuram Thombare
cc3a392d69 i3c: master: fix for SETDASA and DAA process
This patch fix following issue.
Controller slots blocked for devices with static_addr
but no init_dyn_addr may limit the number of I3C devices
on the bus which gets dynamic address in DAA. So
instead of attaching all the devices with static_addr,
now we only attach the devices which successfully
complete SETDASA. For remaining devices with init_dyn_addr,
i3c_master_add_i3c_dev_locked() will try to set requested
dynamic address after DAA.

Signed-off-by: Parshuram Thombare <pthombar@cadence.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-i3c/1598337109-14770-1-git-send-email-pthombar@cadence.com
2020-09-14 09:05:58 +02:00
Parshuram Thombare
9da36a7ec4 i3c: master add i3c_master_attach_boardinfo to preserve boardinfo
Boardinfo was lost if I3C object for devices with boardinfo
available are not created or not added to the I3C device list
because of some failure e.g. SETDASA failed, retrieve info failed etc
This patch adds i3c_master_attach_boardinfo which scan boardinfo list
in the master object and 'attach' it to the I3C device object.

Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Signed-off-by: Parshuram Thombare <pthombar@cadence.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-i3c/1590053542-389-1-git-send-email-pthombar@cadence.com
2020-08-19 09:29:56 +02:00
Nicolas Pitre
b4203ce055 i3c master: GETMRL's 3rd byte is optional even with BCR_IBI_PAYLOAD
According to the I3C spec v1.1 document, GETMRL's payload is 2 bytes,
with an optional 3rd byte if the IBI private payload is larger than
1 byte. The whole GETMRL may also be optional so max_ibi_len already
defaults to 1 if BCR_IBI_PAYLOAD prior to the i3c_master_getmrl_locked()
call.

Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-i3c/nycvar.YSQ.7.76.2004151623060.2671@knanqh.ubzr
2020-04-16 14:27:46 +02:00
Wolfram Sang
c4b9de11d0 i3c: convert to use i2c_new_client_device()
Move away from the deprecated API.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-i3c/20200326211002.13241-2-wsa+renesas@sang-engineering.com
2020-03-29 10:35:50 +02:00
Boris Brezillon
7ec0ddb007 i3c: Add a modalias sysfs attribute
Create a modalias sysfs attribute for i3c devices.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Link: https://lore.kernel.org/linux-i3c/a90f64f830128cd12762153de7828b775574c156.1582796652.git.vitor.soares@synopsys.com
2020-02-28 09:35:52 +01:00
Boris Brezillon
12e21a23cc i3c: Fix MODALIAS uevents
file2alias uses %X formatters. Fix typos in the MODALIAS uevent to print
the part and ext IDs in uppercase.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Link: https://lore.kernel.org/linux-i3c/9ac5f1f8413fbb0481de76b5e43f2f4e1b2dc49f.1582796652.git.vitor.soares@synopsys.com
2020-02-27 16:51:18 +01:00
Wolfram Sang
de8964995c i3c: master: no need to iterate master device twice
We already have the master device in a variable, reuse it.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Vitor Soares <vitor.soares@synopsys.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-i3c/20200214145853.24762-1-wsa+renesas@sang-engineering.com
2020-02-17 23:13:43 +01:00
Benjamin Gaignard
026d8450d4 i3c: master: make i3c_bus_set_mode static
i3c_bus_set_mode function is only used in master.c.
Make it static to avoid warning when compiling with W=1.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-12-09 16:07:39 +01:00
Geert Uytterhoeven
708bc6ec65 i3c: Spelling s/dicovered/discovered/
Fix misspellings of "discovered".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-10-31 11:24:52 +01:00
Vitor Soares
f12b524ea3 i3c: master: use i3c_dev_get_master()
Since we have i3c_dev_get_master() available, use it.

Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-10-01 12:57:30 +02:00
Axel Lin
6030f42d20 i3c: master: Use dev_to_i3cmaster()
Since we have dev_to_i3cmaster() available, use it.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-08-27 09:43:59 +02:00
Wenwen Wang
7afe9a4e56 i3c: master: fix a memory leak bug
In i3c_master_getmwl_locked(), the buffer used for the dest payload data is
allocated using kzalloc() in i3c_ccc_cmd_dest_init(). Later on, the length
of the dest payload data is checked against 'sizeof(*mwl)'. If they are not
equal, -EIO is returned to indicate the error. However, the allocated
buffer is not deallocated on this path, leading to a memory leak.

To fix the above issue, free the buffer before returning the error.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-08-12 10:11:29 +02:00
Przemyslaw Gaj
b1ac3a4b9a i3c: add addr and lvr to i2c_dev_desc structure
I need to store address and lvr value for I2C devices without static definition
in DT. This allows secondary master to transmit DEFSLVS command properly.

Main changes between v4 and v5:
- Change in defslvs to use addr and lvr from i2c_dev_desc structure
- Change in CDNS and DW drivers to use addr and lvr from i2c_dev_desc structure

Signed-off-by: Przemyslaw Gaj <pgaj@cadence.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-08-11 10:48:28 +02:00
Nishka Dasgupta
91227632fc i3c: master: Add of_node_put() before return
Each iteration of for_each_available_childe_of_node puts the previous
node, but in the case of a return from the middle of the loop, there
is no put, thus causing a memory leak. Add an of_node_put before the
return.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-08-11 10:45:51 +02:00
Vitor Soares
934d24a5e1 i3c: move i3c_device_match_id to device.c and export it
Some I3C device drivers need to know which entry matches the
i3c_device object passed to the probe function

Let's move i3c_device_match_id() to device.c and export it so it can be
used by drivers.

Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-07-27 11:22:19 +02:00
Gustavo A. R. Silva
ede2001569 i3c: master: Use struct_size() helper
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes, in particular in the
context in which this code is being used.

So, replace the following form:

sizeof(*defslvs) + ((ndevs - 1) * sizeof(struct i3c_ccc_dev_desc))

with:

struct_size(defslvs, slaves, ndevs - 1)

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-07-04 12:05:14 +02:00
Vitor Soares
cbf4f7325a i3c: add mixed limited bus mode
The i3c bus spec defines a bus configuration where i2c devices don't
have a 50ns filter but support SCL running at SDR max rate (12.5MHz).

This patch introduces the limited bus mode so that users can use
a higher speed in presence of i2c devices index 1.

Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-06-20 09:23:22 +02:00
Vitor Soares
ecc8fb54bd i3c: fix i2c and i3c scl rate by bus mode
Currently the I3C framework limits SCL frequency to FM speed when
dealing with a mixed slow bus, even if all I2C devices are FM+ capable.

The core was also not accounting for I3C speed limitations when
operating in mixed slow mode and was erroneously using FM+ speed as the
max I2C speed when operating in mixed fast mode.

Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <stable@vger.kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-06-20 09:23:22 +02:00
Przemyslaw Gaj
88c5032244 i3c: Drop support for I2C 10 bit addresing
This patch drops support for I2C devices with 10 bit addressing. When I2C
device with 10 bit address is defined in DT, I3C master registration fails.

Address space for I2C devices has been reduced and ->i2c_funcs() hook has been
removed.

Because this patch series dropped support for 10 bit I2C devices, support is
also dropped in Cadence I3C master driver and Synopsys DesignWare I3C master
driver.

Signed-off-by: Przemyslaw Gaj <pgaj@cadence.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-05-28 09:39:53 +02:00
Linus Torvalds
80104bb06b * Fix a shift wrap bug in the core
* Remove dead code in the DW driver
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Merge tag 'i3c/for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux

Pull i3c update from Boris Brezillon:

 - Fix a shift wrap bug in the core

 - Remove dead code in the DW driver

* tag 'i3c/for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux:
  i3c: Fix a shift wrap bug in i3c_bus_set_addr_slot_status()
  i3c: master: dw: remove dead code from dw_i3c_master_*_xfers()
2019-05-07 08:50:40 -07:00
Dan Carpenter
476c7e1d34 i3c: Fix a shift wrap bug in i3c_bus_set_addr_slot_status()
The problem here is that addr can be I3C_BROADCAST_ADDR (126).  That
means we're shifting by (126 * 2) % 64 which is 60.  The
I3C_ADDR_SLOT_STATUS_MASK is an enum which is an unsigned int in GCC
so shifts greater than 31 are undefined.

Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-05-06 08:15:02 +02:00
Vitor Soares
9752c37cc8 i3c: Fix the verification of random PID
The validation of random PID should be done by checking the
boardinfo->pid instead of info.pid which is empty.

Doing the change the info struture declaration is no longer necessary.

Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <stable@vger.kernel.org>
Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
2019-04-10 12:43:47 +02:00
Jisheng Zhang
093c61b6a0 i3c: fix missing detach if failed to retrieve i3c dev
If we failed to retrieve the i3c dev, we should detach the i3c dev
I.E i3c_master_detach_i3c_dev().

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
2019-01-25 08:48:01 +01:00
Dan Carpenter
afe120c777 ic3: off by one in mode_show()
This should be >= ARRAY_SIZE() to avoid reading one element beyond the
end of the array.

Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-12-05 17:22:58 +01:00
Dan Carpenter
840414ae59 i3c: fix an error code in i3c_master_add_i3c_dev_locked()
We should return "ret" as-is.  The "newdev" variable is a valid pointer.

Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-12-05 17:22:58 +01:00
Boris Brezillon
3a379bbcea i3c: Add core I3C infrastructure
Add core infrastructure to support I3C in Linux and document it.

This infrastructure adds basic I3C support. Advanced features will be
added afterwards.

There are a few design choices that are worth mentioning because they
impact the way I3C device drivers can interact with their devices:

- all functions used to send I3C/I2C frames must be called in
  non-atomic context. Mainly done this way to ease implementation, but
  this is not set in stone, and if anyone needs async support, new
  functions can be added later on.
- the bus element is a separate object, but it's tightly coupled with
  the master object. We thus have a 1:1 relationship between i3c_bus
  and i3c_master_controller objects, and if 2 master controllers are
  connected to the same bus and both exposed to the same Linux instance
  they will appear as two distinct busses, and devices on this bus will
  be exposed twice.
- I2C backward compatibility has been designed to be transparent to I2C
  drivers and the I2C subsystem. The I3C master just registers an I2C
  adapter which creates a new I2C bus. I'd say that, from a
  representation PoV it's not ideal because what should appear as a
  single I3C bus exposing I3C and I2C devices here appears as 2
  different buses connected to each other through the parenting (the
  I3C master is the parent of the I2C and I3C busses).
  On the other hand, I don't see a better solution if we want something
  that is not invasive.

Missing features:
- I3C HDR modes are not supported
- no support for multi-master and the associated concepts (mastership
  handover, support for secondary masters, ...)
- I2C devices can only be described using DT because this is the only
  use case I have. However, the framework can easily be extended with
  ACPI and board info support
- I3C slave framework. This has been completely omitted, but shouldn't
  have a huge impact on the I3C framework because I3C slaves don't see
  the whole bus, it's only about handling master requests and generating
  IBIs. Some of the struct, constant and enum definitions could be
  shared, but most of the I3C slave framework logic will be different

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-12 10:33:49 +01:00