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authorLinus Torvalds <torvalds@linux-foundation.org>2020-08-15 08:09:38 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-15 08:09:38 -0700
commit884e0d3dd59dde1c1f0fbb5b9db2bcdc581982c7 (patch)
treebd74dc63722b62823a98ed3fc0bccbb71a4890f6 /drivers/clocksource
parent18737f4243abe02f55ad62ad4baa04c318b48e8d (diff)
parente15d7f2b81d2e7d93115d46fa931b366c1cdebc2 (diff)
Merge tag 'mfd-next-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd
Pull MFD updates from Lee Jones: "Core Frameworks - Make better attempt at matching device with the correct OF node - Allow batch removal of hierarchical sub-devices New Drivers - Add STM32 Clocksource driver - Add support for Khadas System Control Microcontroller Driver Removal - Remove unused driver for TI's SMSC ECE1099 New Device Support - Add support for Intel Emmitsburg PCH to Intel LPSS PCI - Add support for Intel Tiger Lake PCH-H to Intel LPSS PCI - Add support for Dialog DA revision to Dialog DA9063 New Functionality - Add support for AXP803 to be probed by I2C Fix-ups - Numerous W=1 warning fixes - Device Tree changes (stm32-lptimer, gateworks-gsc, khadas,mcu, stmfx, cros-ec, j721e-system-controller) - Enabled Regmap 'fast I/O' in stm32-lptimer - Change BUG_ON to WARN_ON in arizona-core - Remove superfluous code/initialisation (madera, max14577) - Trivial formatting/spelling issues (madera-core, madera-i2c, da9055, max77693-private) - Switch to of_platform_populate() in sprd-sc27xx-spi - Expand out set/get brightness/pwm macros in lm3533-ctrlbank - Disable IRQs on suspend in motorola-cpcap - Clean-up error handling in intel_soc_pmic_mrfld - Ensure correct removal order of sub-devices in madera - Many s/HTTP/HTTPS/ link changes - Ensure name used with Regmap is unique in syscon Bug Fixes - Properly 'put' clock on unbind and error in arizona-core - Fix revision handling in da9063 - Fix 'assignment of read-only location' error in kempld-core - Avoid using the Regmap API when atomic in rn5t618 - Redefine volatile register description in rn5t618 - Use locking to protect event handler in dln2" * tag 'mfd-next-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (76 commits) mfd: syscon: Use a unique name with regmap_config mfd: Replace HTTP links with HTTPS ones mfd: dln2: Run event handler loop under spinlock mfd: madera: Improve handling of regulator unbinding mfd: mfd-core: Add mechanism for removal of a subset of children mfd: intel_soc_pmic_mrfld: Simplify the return expression of intel_scu_ipc_dev_iowrite8() mfd: max14577: Remove redundant initialization of variable current_bits mfd: rn5t618: Fix caching of battery related registers mfd: max77693-private: Drop a duplicated word mfd: da9055: pdata.h: Drop a duplicated word mfd: rn5t618: Make restart handler atomic safe mfd: kempld-core: Fix 'assignment of read-only location' error mfd: axp20x: Allow the AXP803 to be probed by I2C mfd: da9063: Add support for latest DA silicon revision mfd: da9063: Fix revision handling to correctly select reg tables dt-bindings: mfd: st,stmfx: Remove I2C unit name dt-bindings: mfd: ti,j721e-system-controller.yaml: Add J721e system controller mfd: motorola-cpcap: Disable interrupt for suspend mfd: smsc-ece1099: Remove driver mfd: core: Add OF_MFD_CELL_REG() helper ...
Diffstat (limited to 'drivers/clocksource')
-rw-r--r--drivers/clocksource/Kconfig4
-rw-r--r--drivers/clocksource/Makefile1
-rw-r--r--drivers/clocksource/timer-stm32-lp.c221
3 files changed, 226 insertions, 0 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 2ed8b4361d95..3576ad7bd380 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -291,6 +291,10 @@ config CLKSRC_STM32
select CLKSRC_MMIO
select TIMER_OF
+config CLKSRC_STM32_LP
+ bool "Low power clocksource for STM32 SoCs"
+ depends on MFD_STM32_LPTIMER || COMPILE_TEST
+
config CLKSRC_MPS2
bool "Clocksource for MPS2 SoCs" if COMPILE_TEST
depends on GENERIC_SCHED_CLOCK
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 3994e221e262..eaedb7240ae7 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -45,6 +45,7 @@ obj-$(CONFIG_BCM_KONA_TIMER) += bcm_kona_timer.o
obj-$(CONFIG_CADENCE_TTC_TIMER) += timer-cadence-ttc.o
obj-$(CONFIG_CLKSRC_EFM32) += timer-efm32.o
obj-$(CONFIG_CLKSRC_STM32) += timer-stm32.o
+obj-$(CONFIG_CLKSRC_STM32_LP) += timer-stm32-lp.o
obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o
obj-$(CONFIG_CLKSRC_LPC32XX) += timer-lpc32xx.o
obj-$(CONFIG_CLKSRC_MPS2) += mps2-timer.o
diff --git a/drivers/clocksource/timer-stm32-lp.c b/drivers/clocksource/timer-stm32-lp.c
new file mode 100644
index 000000000000..db2841d0beb8
--- /dev/null
+++ b/drivers/clocksource/timer-stm32-lp.c
@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics 2019 - All Rights Reserved
+ * Authors: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
+ * Pascal Paillet <p.paillet@st.com> for STMicroelectronics.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/stm32-lptimer.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/pm_wakeirq.h>
+
+#define CFGR_PSC_OFFSET 9
+#define STM32_LP_RATING 1000
+#define STM32_TARGET_CLKRATE (32000 * HZ)
+#define STM32_LP_MAX_PSC 7
+
+struct stm32_lp_private {
+ struct regmap *reg;
+ struct clock_event_device clkevt;
+ unsigned long period;
+ struct device *dev;
+};
+
+static struct stm32_lp_private*
+to_priv(struct clock_event_device *clkevt)
+{
+ return container_of(clkevt, struct stm32_lp_private, clkevt);
+}
+
+static int stm32_clkevent_lp_shutdown(struct clock_event_device *clkevt)
+{
+ struct stm32_lp_private *priv = to_priv(clkevt);
+
+ regmap_write(priv->reg, STM32_LPTIM_CR, 0);
+ regmap_write(priv->reg, STM32_LPTIM_IER, 0);
+ /* clear pending flags */
+ regmap_write(priv->reg, STM32_LPTIM_ICR, STM32_LPTIM_ARRMCF);
+
+ return 0;
+}
+
+static int stm32_clkevent_lp_set_timer(unsigned long evt,
+ struct clock_event_device *clkevt,
+ int is_periodic)
+{
+ struct stm32_lp_private *priv = to_priv(clkevt);
+
+ /* disable LPTIMER to be able to write into IER register*/
+ regmap_write(priv->reg, STM32_LPTIM_CR, 0);
+ /* enable ARR interrupt */
+ regmap_write(priv->reg, STM32_LPTIM_IER, STM32_LPTIM_ARRMIE);
+ /* enable LPTIMER to be able to write into ARR register */
+ regmap_write(priv->reg, STM32_LPTIM_CR, STM32_LPTIM_ENABLE);
+ /* set next event counter */
+ regmap_write(priv->reg, STM32_LPTIM_ARR, evt);
+
+ /* start counter */
+ if (is_periodic)
+ regmap_write(priv->reg, STM32_LPTIM_CR,
+ STM32_LPTIM_CNTSTRT | STM32_LPTIM_ENABLE);
+ else
+ regmap_write(priv->reg, STM32_LPTIM_CR,
+ STM32_LPTIM_SNGSTRT | STM32_LPTIM_ENABLE);
+
+ return 0;
+}
+
+static int stm32_clkevent_lp_set_next_event(unsigned long evt,
+ struct clock_event_device *clkevt)
+{
+ return stm32_clkevent_lp_set_timer(evt, clkevt,
+ clockevent_state_periodic(clkevt));
+}
+
+static int stm32_clkevent_lp_set_periodic(struct clock_event_device *clkevt)
+{
+ struct stm32_lp_private *priv = to_priv(clkevt);
+
+ return stm32_clkevent_lp_set_timer(priv->period, clkevt, true);
+}
+
+static int stm32_clkevent_lp_set_oneshot(struct clock_event_device *clkevt)
+{
+ struct stm32_lp_private *priv = to_priv(clkevt);
+
+ return stm32_clkevent_lp_set_timer(priv->period, clkevt, false);
+}
+
+static irqreturn_t stm32_clkevent_lp_irq_handler(int irq, void *dev_id)
+{
+ struct clock_event_device *clkevt = (struct clock_event_device *)dev_id;
+ struct stm32_lp_private *priv = to_priv(clkevt);
+
+ regmap_write(priv->reg, STM32_LPTIM_ICR, STM32_LPTIM_ARRMCF);
+
+ if (clkevt->event_handler)
+ clkevt->event_handler(clkevt);
+
+ return IRQ_HANDLED;
+}
+
+static void stm32_clkevent_lp_set_prescaler(struct stm32_lp_private *priv,
+ unsigned long *rate)
+{
+ int i;
+
+ for (i = 0; i <= STM32_LP_MAX_PSC; i++) {
+ if (DIV_ROUND_CLOSEST(*rate, 1 << i) < STM32_TARGET_CLKRATE)
+ break;
+ }
+
+ regmap_write(priv->reg, STM32_LPTIM_CFGR, i << CFGR_PSC_OFFSET);
+
+ /* Adjust rate and period given the prescaler value */
+ *rate = DIV_ROUND_CLOSEST(*rate, (1 << i));
+ priv->period = DIV_ROUND_UP(*rate, HZ);
+}
+
+static void stm32_clkevent_lp_init(struct stm32_lp_private *priv,
+ struct device_node *np, unsigned long rate)
+{
+ priv->clkevt.name = np->full_name;
+ priv->clkevt.cpumask = cpu_possible_mask;
+ priv->clkevt.features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT;
+ priv->clkevt.set_state_shutdown = stm32_clkevent_lp_shutdown;
+ priv->clkevt.set_state_periodic = stm32_clkevent_lp_set_periodic;
+ priv->clkevt.set_state_oneshot = stm32_clkevent_lp_set_oneshot;
+ priv->clkevt.set_next_event = stm32_clkevent_lp_set_next_event;
+ priv->clkevt.rating = STM32_LP_RATING;
+
+ clockevents_config_and_register(&priv->clkevt, rate, 0x1,
+ STM32_LPTIM_MAX_ARR);
+}
+
+static int stm32_clkevent_lp_probe(struct platform_device *pdev)
+{
+ struct stm32_lptimer *ddata = dev_get_drvdata(pdev->dev.parent);
+ struct stm32_lp_private *priv;
+ unsigned long rate;
+ int ret, irq;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->reg = ddata->regmap;
+ ret = clk_prepare_enable(ddata->clk);
+ if (ret)
+ return -EINVAL;
+
+ rate = clk_get_rate(ddata->clk);
+ if (!rate) {
+ ret = -EINVAL;
+ goto out_clk_disable;
+ }
+
+ irq = platform_get_irq(to_platform_device(pdev->dev.parent), 0);
+ if (irq <= 0) {
+ ret = irq;
+ goto out_clk_disable;
+ }
+
+ if (of_property_read_bool(pdev->dev.parent->of_node, "wakeup-source")) {
+ ret = device_init_wakeup(&pdev->dev, true);
+ if (ret)
+ goto out_clk_disable;
+
+ ret = dev_pm_set_wake_irq(&pdev->dev, irq);
+ if (ret)
+ goto out_clk_disable;
+ }
+
+ ret = devm_request_irq(&pdev->dev, irq, stm32_clkevent_lp_irq_handler,
+ IRQF_TIMER, pdev->name, &priv->clkevt);
+ if (ret)
+ goto out_clk_disable;
+
+ stm32_clkevent_lp_set_prescaler(priv, &rate);
+
+ stm32_clkevent_lp_init(priv, pdev->dev.parent->of_node, rate);
+
+ priv->dev = &pdev->dev;
+
+ return 0;
+
+out_clk_disable:
+ clk_disable_unprepare(ddata->clk);
+ return ret;
+}
+
+static int stm32_clkevent_lp_remove(struct platform_device *pdev)
+{
+ return -EBUSY; /* cannot unregister clockevent */
+}
+
+static const struct of_device_id stm32_clkevent_lp_of_match[] = {
+ { .compatible = "st,stm32-lptimer-timer", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, stm32_clkevent_lp_of_match);
+
+static struct platform_driver stm32_clkevent_lp_driver = {
+ .probe = stm32_clkevent_lp_probe,
+ .remove = stm32_clkevent_lp_remove,
+ .driver = {
+ .name = "stm32-lptimer-timer",
+ .of_match_table = of_match_ptr(stm32_clkevent_lp_of_match),
+ },
+};
+module_platform_driver(stm32_clkevent_lp_driver);
+
+MODULE_ALIAS("platform:stm32-lptimer-timer");
+MODULE_DESCRIPTION("STMicroelectronics STM32 clockevent low power driver");
+MODULE_LICENSE("GPL v2");