summaryrefslogtreecommitdiff
path: root/drivers/pwm/pwm-meson.c
AgeCommit message (Collapse)AuthorFilesLines
2019-05-10Merge tag 'pwm/for-5.2-rc1' of ↵Linus Torvalds1-15/+49
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm Pull pwm updates from Thierry Reding: "Nothing out of the ordinary this cycle. The bulk of this is a collection of fixes for existing drivers and some cleanups. There's one new driver for i.MX SoCs and addition of support for some new variants to existing drivers" * tag 'pwm/for-5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: pwm: meson: Add clock source configuration for Meson G12A dt-bindings: pwm: Update bindings for the Meson G12A Family pwm: samsung: Don't uses devm_*() functions in ->request() pwm: Clear chip_data in pwm_put() pwm: Add i.MX TPM PWM driver support dt-bindings: pwm: Add i.MX TPM PWM binding pwm: imx27: Use devm_platform_ioremap_resource() to simplify code pwm: meson: Use the spin-lock only to protect register modifications pwm: meson: Don't disable PWM when setting duty repeatedly pwm: meson: Consider 128 a valid pre-divider pwm: sysfs: fix typo "its" -> "it's" pwm: tiehrpwm: Enable compilation for ARCH_K3 dt-bindings: pwm: tiehrpwm: Add TI AM654 SoC specific compatible pwm: tiehrpwm: Update shadow register for disabling PWMs pwm: img: Turn final 'else if' into 'else' in img_pwm_config pwm: Fix deadlock warning when removing PWM device
2019-05-09pwm: meson: Add clock source configuration for Meson G12ANeil Armstrong1-0/+30
For the PWM controller in the Meson G12A SoC, the EE domain and AO domain have different clock sources. This patch tries to describe them in the DT compatible data. The two AO PWM controller has different clock source, but the first AO controller (A & B) can reuse the AXG parents name. Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-05-09pwm: meson: Use the spin-lock only to protect register modificationsMartin Blumenstingl1-8/+17
Holding the spin-lock for all of the code in meson_pwm_apply() can result in a "BUG: scheduling while atomic". This can happen because clk_get_rate() (which is called from meson_pwm_calc()) may sleep. Only hold the spin-lock when modifying registers to solve this. The reason why we need a spin-lock in the driver is because the REG_MISC_AB register is shared between the two channels provided by one PWM controller. The only functions where REG_MISC_AB is modified are meson_pwm_enable() and meson_pwm_disable() so the register reads/writes in there need to be protected by the spin-lock. The original code also used the spin-lock to protect the values in struct meson_pwm_channel. This could be necessary if two consumers can use the same PWM channel. However, PWM core doesn't allow this so we don't need to protect the values in struct meson_pwm_channel with a lock. Fixes: 211ed630753d2f ("pwm: Add support for Meson PWM Controller") Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-05-09pwm: meson: Don't disable PWM when setting duty repeatedlyBichao Zheng1-5/+0
There is an abnormally low about 20ms,when setting duty repeatedly. Because setting the duty will disable PWM and then enable. Delete this operation now. Fixes: 211ed630753d2f ("pwm: Add support for Meson PWM Controller") Signed-off-by: Bichao Zheng <bichao.zheng@amlogic.com> [ Dropped code instead of hiding it behind a comment ] Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Reviewed-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-05-09pwm: meson: Consider 128 a valid pre-dividerMartin Blumenstingl1-2/+2
The pre-divider allows configuring longer PWM periods compared to using the input clock directly. The pre-divider is 7 bit wide, meaning it's maximum value is 128 (the register value is off-by-one: 0x7f or 127). Change the loop to also allow for the maximum possible value to be considered valid. Fixes: 211ed630753d2f ("pwm: Add support for Meson PWM Controller") Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-04-26clk: Remove CLK_IS_BASIC clk flagStephen Boyd1-1/+1
This flag was historically used to indicate that a clk is a "basic" type of clk like a mux, divider, gate, etc. This never turned out to be very useful though because it was hard to cleanly split "basic" clks from other clks in a system. This one flag was a way for type introspection and it just didn't scale. If anything, it was used by the TI clk driver to indicate that a clk_hw wasn't contained in the SoC specific clk structure. We can get rid of this define now that TI is finding those clks a different way. Cc: Tero Kristo <t-kristo@ti.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: James Hogan <jhogan@kernel.org> Cc: <linux-mips@vger.kernel.org> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Kevin Hilman <khilman@baylibre.com> Cc: <linux-pwm@vger.kernel.org> Cc: <linux-amlogic@lists.infradead.org> Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2018-08-20pwm: meson: Fix mux clock namesJerome Brunet1-2/+1
Current clock name looks like this: /soc/bus@ffd00000/pwm@1b000#mux0 This is bad because CCF uses the clock to create a directory in clk debugfs. With such name, the directory creation (silently) fails and the debugfs entry end up being created at the debugfs root. With this change, the clock name will now be: ffd1b000.pwm#mux0 This matches the clock naming scheme used in the ethernet and mmc driver. It also fixes the problem with debugfs. Fixes: 36af66a79056 ("pwm: Convert to using %pOF instead of full_name") Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2018-04-30pwm: meson: Fix allocation of PWM channel arrayMartin Blumenstingl1-2/+2
Using the pwm-meson driver on the 32-bit SoCs causes memory corruption. The result are some hard-to-explain errors, for example devm_clk_register() crashes with a NULL dereference somewhere deep in the common clock framework code. In some cases the kernel even refused to boot when any of the PWM controllers were enabled on Meson8b. The root cause is an incorrect memory size in the devm_kcalloc() call in meson_pwm_probe(). The code allocates an array of meson_pwm_channel structs, but the size given is the size of the meson_pwm struct (which seems like a small copy-and-paste error, as meson_pwm is allocated a few lines above). Even with this typo the code seemed to work fine on the 64-bit GX SoCs (maybe due to the structs having the same size in the compiled result, but I haven't checked this further). Fixes: 211ed630753d2f ("pwm: Add support for Meson PWM Controller") Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2017-12-05pwm: meson: Add clock source configuration for Meson-AXGJian Hu1-0/+26
For PWM controller in the Meson-AXG SoC, the EE domain and AO domain have different clock sources. This patch tries to describe them in the DT compatible data. Signed-off-by: Jian Hu <jian.hu@amlogic.com> Signed-off-by: Yixun Lan <yixun.lan@amlogic.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2017-07-25pwm: Convert to using %pOF instead of full_nameRob Herring1-1/+1
Now that we have a custom printf format specifier, convert users of full_name to use %pOF instead. This is preparation to remove storing of the full path string for each node. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Carlo Caione <carlo@caione.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: linux-pwm@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-amlogic@lists.infradead.org Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2017-07-06pwm: meson: Improve PWM calculation precisionJerome Brunet1-6/+10
When using input clocks with high rates, such as clk81 (166MHz), the fin_ns = NSEC_PER_SEC / fin_freq can introduce a significant error. Ex: fin_freq = 166666667, NSEC_PER_SEC = 1000000000 fin_ns = 5,9999999 which is, of course, rounded down to 5. This introduces an error of ~20% on the period requested from the PWM. This patch uses ps instead of ns (and 64 bit integers) to perform the calculation. This should give a good enough precision. Fixes: 211ed630753d ("pwm: Add support for Meson PWM Controller") Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> squash! pwm: meson: Improve pwm calculation precision
2017-07-06pwm: meson: Add compatible for the gxbb ao PWMsJerome Brunet1-3/+29
On the gxbb (and gxl) family, the PWMs of the AO domain require a specific compatible because the possible input clocks are different from the EE PWMs input clocks. Since the number of possible input clocks is also different, the 'num_parents' field is added to all the Meson PWM data. Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-12-15Merge tag 'pwm/for-4.10-rc1' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm Pull pwm updates from Thierry Reding: "This is a very tiny pull request, with just a new driver for HiSilicon BVT SoCs and a cleanup for the Amlogic Meson driver. There are other patches on the list, but my timing was really bad this time and I ended up not having the time to look at them in enough detail to be comfortable merging them" * tag 'pwm/for-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: pwm: Add PWM driver for HiSilicon BVT SOCs pwm: meson: Remove unneeded platform MODULE_ALIAS
2016-10-21pwm: meson: Remove unneeded platform MODULE_ALIASJavier Martinez Canillas1-1/+0
The Amlogic Meson is a DT-only platform, which means the devices are registered via OF and not using the legacy platform devices support. So there's no need to have a MODULE_ALIAS("platform:meson-pwm") since the reported uevent MODALIAS to user-space will always be the OF one. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Acked-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-10-21pwm: meson: Add missing spin_lock_init()Axel Lin1-0/+1
The driver uses the spin_lock but does not initialize it. Fix it. Signed-off-by: Axel Lin <axel.lin@ingics.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-09-08pwm: meson: Handle unknown ID valuesArnd Bergmann1-0/+9
When building with -Wmaybe-uninitialized, we get a couple of harmless warnings about three functions in this new driver that don't look safe to the compiler: drivers/pwm/pwm-meson.c: In function 'meson_pwm_get_state': drivers/pwm/pwm-meson.c:355:26: error: 'mask' may be used uninitialized in this function [-Werror=maybe-uninitialized] drivers/pwm/pwm-meson.c: In function 'meson_pwm_disable': drivers/pwm/pwm-meson.c:263:13: error: 'enable' may be used uninitialized in this function [-Werror=maybe-uninitialized] drivers/pwm/pwm-meson.c: In function 'meson_pwm_apply': drivers/pwm/pwm-meson.c:231:13: error: 'clk_shift' may be used uninitialized in this function [-Werror=maybe-uninitialized] drivers/pwm/pwm-meson.c:231:36: error: 'enable' may be used uninitialized in this function [-Werror=maybe-uninitialized] drivers/pwm/pwm-meson.c:231:24: error: 'clk_enable' may be used uninitialized in this function [-Werror=maybe-uninitialized] Specifically, if we have a device with an ID other than 0 or 1, this would result in undefined behavior. This is currently not possible, but the compiler cannot be expected to know this. This patch adds a 'default' clause to let the compiler know what to do instead, which shuts up the warning and makes the code slightly more resiliant in case it gets extended to other identifiers. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-09-08pwm: Add support for Meson PWM ControllerNeil Armstrong1-0/+520
Add support for the PWM controller found in the Amlogic SoCs. This driver supports the Meson8b and GXBB SoCs. Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Tested-by: Jerome Brunet <jbrunet@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>