diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-04-26 12:11:52 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-04-26 12:11:52 -0700 |
commit | 37f00ab4a003f371f81e0eae76cf372f06dec780 (patch) | |
tree | c6217483f22a0fac876f12af53f4b8948200f2fd /drivers/pwm/pwm-raspberrypi-poe.c | |
parent | 2b90506a8186df5f7c81ad1ebd250103d8469e27 (diff) | |
parent | 5ffa828534036348fa90fb3079ccc0972d202c4a (diff) |
Merge tag 'arm-drivers-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC driver updates from Arnd Bergmann:
"Updates for SoC specific drivers include a few subsystems that have
their own maintainers but send them through the soc tree:
TEE/OP-TEE:
- Add tracepoints around calls to secure world
Memory controller drivers:
- Minor fixes for Renesas, Exynos, Mediatek and Tegra platforms
- Add debug statistics to Tegra20 memory controller
- Update Tegra bindings and convert to dtschema
ARM SCMI Firmware:
- Support for modular SCMI protocols and vendor specific extensions
- New SCMI IIO driver
- Per-cpu DVFS
The other driver changes are all from the platform maintainers
directly and reflect the drivers that don't fit into any other
subsystem as well as treewide changes for a particular platform.
SoCFPGA:
- Various cleanups contributed by Krzysztof Kozlowski
Mediatek:
- add MT8183 support to mutex driver
- MMSYS: use per SoC array to describe the possible routing
- add MMSYS support for MT8183 and MT8167
- add support for PMIC wrapper with integrated arbiter
- add support for MT8192/MT6873
Tegra:
- Bug fixes to PMC and clock drivers
NXP/i.MX:
- Update SCU power domain driver to keep console domain power on.
- Add missing ADC1 power domain to SCU power domain driver.
- Update comments for single global power domain in SCU power domain
driver.
- Add i.MX51/i.MX53 unique id support to i.MX SoC driver.
NXP/FSL SoC driver updates for v5.13
- Add ACPI support for RCPM driver
- Use generic io{read,write} for QE drivers after performance
optimized for PowerPC
- Fix QBMAN probe to cleanup HW states correctly for kexec
- Various cleanup and style fix for QBMAN/QE/GUTS drivers
OMAP:
- Preparation to use devicetree for genpd
- ti-sysc needs iorange check improved when the interconnect target
module has no control registers listed
- ti-sysc needs to probe l4_wkup and l4_cfg interconnects first to
avoid issues with missing resources and unnecessary deferred probe
- ti-sysc debug option can now detect more devices
- ti-sysc now warns if an old incomplete devicetree data is found as
we now rely on it being complete for am3 and 4
- soc init code needs to check for prcm and prm nodes for omap4/5 and
dra7
- omap-prm driver needs to enable autoidle retention support for
omap4
- omap5 clocks are missing gpmc and ocmc clock registers
- pci-dra7xx now needs to use builtin_platform_driver instead of
using builtin_platform_driver_probe for deferred probe to work
Raspberry Pi:
- Fix-up all RPi firmware drivers so as for unbind to happen in an
orderly fashion
- Support for RPi's PoE hat PWM bus
Qualcomm
- Improved detection for SCM calling conventions
- Support for OEM specific wifi firmware path
- Added drivers for SC7280/SM8350: RPMH, LLCC< AOSS QMP"
* tag 'arm-drivers-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (165 commits)
soc: aspeed: fix a ternary sign expansion bug
memory: mtk-smi: Add device-link between smi-larb and smi-common
memory: samsung: exynos5422-dmc: handle clk_set_parent() failure
memory: renesas-rpc-if: fix possible NULL pointer dereference of resource
clk: socfpga: fix iomem pointer cast on 64-bit
soc: aspeed: Adapt to new LPC device tree layout
pinctrl: aspeed-g5: Adapt to new LPC device tree layout
ipmi: kcs: aspeed: Adapt to new LPC DTS layout
ARM: dts: Remove LPC BMC and Host partitions
dt-bindings: aspeed-lpc: Remove LPC partitioning
soc: fsl: enable acpi support in RCPM driver
soc: qcom: mdt_loader: Detect truncated read of segments
soc: qcom: mdt_loader: Validate that p_filesz < p_memsz
soc: qcom: pdr: Fix error return code in pdr_register_listener
firmware: qcom_scm: Fix kernel-doc function names to match
firmware: qcom_scm: Suppress sysfs bind attributes
firmware: qcom_scm: Workaround lack of "is available" call on SC7180
firmware: qcom_scm: Reduce locking section for __get_convention()
firmware: qcom_scm: Make __qcom_scm_is_call_available() return bool
Revert "soc: fsl: qe: introduce qe_io{read,write}* wrappers"
...
Diffstat (limited to 'drivers/pwm/pwm-raspberrypi-poe.c')
-rw-r--r-- | drivers/pwm/pwm-raspberrypi-poe.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-raspberrypi-poe.c b/drivers/pwm/pwm-raspberrypi-poe.c new file mode 100644 index 000000000000..043fc32e8be8 --- /dev/null +++ b/drivers/pwm/pwm-raspberrypi-poe.c @@ -0,0 +1,206 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2021 Nicolas Saenz Julienne <nsaenzjulienne@suse.de> + * For more information on Raspberry Pi's PoE hat see: + * https://www.raspberrypi.org/products/poe-hat/ + * + * Limitations: + * - No disable bit, so a disabled PWM is simulated by duty_cycle 0 + * - Only normal polarity + * - Fixed 12.5 kHz period + * + * The current period is completed when HW is reconfigured. + */ + +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> + +#include <soc/bcm2835/raspberrypi-firmware.h> +#include <dt-bindings/pwm/raspberrypi,firmware-poe-pwm.h> + +#define RPI_PWM_MAX_DUTY 255 +#define RPI_PWM_PERIOD_NS 80000 /* 12.5 kHz */ + +#define RPI_PWM_CUR_DUTY_REG 0x0 + +struct raspberrypi_pwm { + struct rpi_firmware *firmware; + struct pwm_chip chip; + unsigned int duty_cycle; +}; + +struct raspberrypi_pwm_prop { + __le32 reg; + __le32 val; + __le32 ret; +} __packed; + +static inline +struct raspberrypi_pwm *raspberrypi_pwm_from_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct raspberrypi_pwm, chip); +} + +static int raspberrypi_pwm_set_property(struct rpi_firmware *firmware, + u32 reg, u32 val) +{ + struct raspberrypi_pwm_prop msg = { + .reg = cpu_to_le32(reg), + .val = cpu_to_le32(val), + }; + int ret; + + ret = rpi_firmware_property(firmware, RPI_FIRMWARE_SET_POE_HAT_VAL, + &msg, sizeof(msg)); + if (ret) + return ret; + if (msg.ret) + return -EIO; + + return 0; +} + +static int raspberrypi_pwm_get_property(struct rpi_firmware *firmware, + u32 reg, u32 *val) +{ + struct raspberrypi_pwm_prop msg = { + .reg = reg + }; + int ret; + + ret = rpi_firmware_property(firmware, RPI_FIRMWARE_GET_POE_HAT_VAL, + &msg, sizeof(msg)); + if (ret) + return ret; + if (msg.ret) + return -EIO; + + *val = le32_to_cpu(msg.val); + + return 0; +} + +static void raspberrypi_pwm_get_state(struct pwm_chip *chip, + struct pwm_device *pwm, + struct pwm_state *state) +{ + struct raspberrypi_pwm *rpipwm = raspberrypi_pwm_from_chip(chip); + + state->period = RPI_PWM_PERIOD_NS; + state->duty_cycle = DIV_ROUND_UP(rpipwm->duty_cycle * RPI_PWM_PERIOD_NS, + RPI_PWM_MAX_DUTY); + state->enabled = !!(rpipwm->duty_cycle); + state->polarity = PWM_POLARITY_NORMAL; +} + +static int raspberrypi_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct raspberrypi_pwm *rpipwm = raspberrypi_pwm_from_chip(chip); + unsigned int duty_cycle; + int ret; + + if (state->period < RPI_PWM_PERIOD_NS || + state->polarity != PWM_POLARITY_NORMAL) + return -EINVAL; + + if (!state->enabled) + duty_cycle = 0; + else if (state->duty_cycle < RPI_PWM_PERIOD_NS) + duty_cycle = DIV_ROUND_DOWN_ULL(state->duty_cycle * RPI_PWM_MAX_DUTY, + RPI_PWM_PERIOD_NS); + else + duty_cycle = RPI_PWM_MAX_DUTY; + + if (duty_cycle == rpipwm->duty_cycle) + return 0; + + ret = raspberrypi_pwm_set_property(rpipwm->firmware, RPI_PWM_CUR_DUTY_REG, + duty_cycle); + if (ret) { + dev_err(chip->dev, "Failed to set duty cycle: %pe\n", + ERR_PTR(ret)); + return ret; + } + + rpipwm->duty_cycle = duty_cycle; + + return 0; +} + +static const struct pwm_ops raspberrypi_pwm_ops = { + .get_state = raspberrypi_pwm_get_state, + .apply = raspberrypi_pwm_apply, + .owner = THIS_MODULE, +}; + +static int raspberrypi_pwm_probe(struct platform_device *pdev) +{ + struct device_node *firmware_node; + struct device *dev = &pdev->dev; + struct rpi_firmware *firmware; + struct raspberrypi_pwm *rpipwm; + int ret; + + firmware_node = of_get_parent(dev->of_node); + if (!firmware_node) { + dev_err(dev, "Missing firmware node\n"); + return -ENOENT; + } + + firmware = devm_rpi_firmware_get(&pdev->dev, firmware_node); + of_node_put(firmware_node); + if (!firmware) + return dev_err_probe(dev, -EPROBE_DEFER, + "Failed to get firmware handle\n"); + + rpipwm = devm_kzalloc(&pdev->dev, sizeof(*rpipwm), GFP_KERNEL); + if (!rpipwm) + return -ENOMEM; + + rpipwm->firmware = firmware; + rpipwm->chip.dev = dev; + rpipwm->chip.ops = &raspberrypi_pwm_ops; + rpipwm->chip.base = -1; + rpipwm->chip.npwm = RASPBERRYPI_FIRMWARE_PWM_NUM; + + platform_set_drvdata(pdev, rpipwm); + + ret = raspberrypi_pwm_get_property(rpipwm->firmware, RPI_PWM_CUR_DUTY_REG, + &rpipwm->duty_cycle); + if (ret) { + dev_err(dev, "Failed to get duty cycle: %pe\n", ERR_PTR(ret)); + return ret; + } + + return pwmchip_add(&rpipwm->chip); +} + +static int raspberrypi_pwm_remove(struct platform_device *pdev) +{ + struct raspberrypi_pwm *rpipwm = platform_get_drvdata(pdev); + + return pwmchip_remove(&rpipwm->chip); +} + +static const struct of_device_id raspberrypi_pwm_of_match[] = { + { .compatible = "raspberrypi,firmware-poe-pwm", }, + { } +}; +MODULE_DEVICE_TABLE(of, raspberrypi_pwm_of_match); + +static struct platform_driver raspberrypi_pwm_driver = { + .driver = { + .name = "raspberrypi-poe-pwm", + .of_match_table = raspberrypi_pwm_of_match, + }, + .probe = raspberrypi_pwm_probe, + .remove = raspberrypi_pwm_remove, +}; +module_platform_driver(raspberrypi_pwm_driver); + +MODULE_AUTHOR("Nicolas Saenz Julienne <nsaenzjulienne@suse.de>"); +MODULE_DESCRIPTION("Raspberry Pi Firmware Based PWM Bus Driver"); +MODULE_LICENSE("GPL v2"); |