summaryrefslogtreecommitdiff
path: root/drivers/i2c/busses/i2c-microchip-corei2c.c
AgeCommit message (Collapse)Author
2024-12-26i2c: microchip-core: fix "ghost" detectionsConor Dooley
Running i2c-detect currently produces an output akin to: 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: 08 -- 0a -- 0c -- 0e -- 10: 10 -- 12 -- 14 -- 16 -- UU 19 -- 1b -- 1d -- 1f 20: -- 21 -- 23 -- 25 -- 27 -- 29 -- 2b -- 2d -- 2f 30: -- -- -- -- -- -- -- -- 38 -- 3a -- 3c -- 3e -- 40: 40 -- 42 -- 44 -- 46 -- 48 -- 4a -- 4c -- 4e -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: 60 -- 62 -- 64 -- 66 -- 68 -- 6a -- 6c -- 6e -- 70: 70 -- 72 -- 74 -- 76 -- This happens because for an i2c_msg with a len of 0 the driver will mark the transmission of the message as a success once the START has been sent, without waiting for the devices on the bus to respond with an ACK/NAK. Since i2cdetect seems to run in a tight loop over all addresses the NAK is treated as part of the next test for the next address. Delete the fast path that marks a message as complete when idev->msg_len is zero after sending a START/RESTART since this isn't a valid scenario. CC: stable@vger.kernel.org Fixes: 64a6f1c4987e ("i2c: add support for microchip fpga i2c controllers") Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Link: https://lore.kernel.org/r/20241218-outbid-encounter-b2e78b1cc707@spud Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
2024-12-26i2c: microchip-core: actually use repeated sendsConor Dooley
At present, where repeated sends are intended to be used, the i2c-microchip-core driver sends a stop followed by a start. Lots of i2c devices must not malfunction in the face of this behaviour, because the driver has operated like this for years! Try to keep track of whether or not a repeated send is required, and suppress sending a stop in these cases. CC: stable@vger.kernel.org Fixes: 64a6f1c4987e ("i2c: add support for microchip fpga i2c controllers") Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Link: https://lore.kernel.org/r/20241218-football-composure-e56df2461461@spud Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
2024-11-17i2c: Switch back to struct platform_driver::remove()Uwe Kleine-König
After commit 0edb555a65d1 ("platform: Make platform_driver::remove() return void") .remove() is (again) the right callback to implement for platform drivers. Convert all platform drivers below drivers/i2c to use .remove(), with the eventual goal to drop struct platform_driver::remove_new(). As .remove() and .remove_new() have the same prototypes, conversion is done by just changing the structure member name in the driver initializer. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
2023-08-08i2c: remove redundant dev_err_probe()Zhu Wang
When platform_get_irq() is called, the error message has been printed, so it need not to call dev_err_probe() to print error. As the comment of platform_get_irq() says, it returned non-zero value when it succeeded, and it returned negative value when it failed. Signed-off-by: Zhu Wang <wangzhu9@huawei.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230801134814.247782-1-wangzhu9@huawei.com Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
2023-06-05i2c: Convert to platform remove callback returning voidUwe Kleine-König
The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is (mostly) ignored and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new() which already returns void. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Alain Volmat <alain.volmat@foss.st.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Baruch Siach <baruch@tkos.co.il> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> Acked-by: Jochen Friedrich <jochen@scram.de> Acked-by: Peter Rosin <peda@axentia.se> Acked-by: Vadim Pasternak <vadimp@nvidia.com> Reviewed-by: Asmaa Mnebhi <asnaa@nvidia.com> Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Reviewed-by: Chris Pringle <chris.pringle@phabrix.com> Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com> Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> Reviewed-by: Tali Perry <tali.perry@nuvoton.com> Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-08-11i2c: microchip-corei2c: fix erroneous late ack sendConor Dooley
A late ack is currently being sent at the end of a transfer due to incorrect logic in mchp_corei2c_empty_rx(). Currently the Assert Ack bit is being written to the controller's control reg after the last byte has been received, causing it to sent another byte with the ack. Instead, the AA flag should be written to the control register when the penultimate byte is read so it is sent out for the last byte. Reported-by: Andreas Buerkler <andreas.buerkler@enclustra.com> Fixes: 64a6f1c4987e ("i2c: add support for microchip fpga i2c controllers") Tested-by: Lewis Hanly <lewis.hanly@microchip.com> Signed-off-by: Conor Dooley <conor.dooley@microchip.com> [wsa: fixed typos in commit message] Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-07-07i2c: add support for microchip fpga i2c controllersConor Dooley
Add Microchip CoreI2C i2c controller support. This driver supports the "hard" i2c controller on the Microchip PolarFire SoC & the basic feature set for "soft" i2c controller implemtations in the FPGA fabric. Co-developed-by: Daire McNamara <daire.mcnamara@microchip.com> Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com> Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>