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authorIngo Molnar <mingo@kernel.org>2012-08-21 11:27:00 +0200
committerIngo Molnar <mingo@kernel.org>2012-08-21 11:27:00 +0200
commitbcada3d4b8c96b8792c2306f363992ca5ab9da42 (patch)
treee420679a5db6ea4e1694eef57f9abb6acac8d4d3 /drivers/pwm/pwm-lpc32xx.c
parent26198c21d1b286a084fe5d514a30bc7e6c712a34 (diff)
parent000078bc3ee69efb1124b8478c7527389a826074 (diff)
Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: * Fix include order for bison/flex-generated C files, from Ben Hutchings * Build fixes and documentation corrections from David Ahern * Group parsing support, from Jiri Olsa * UI/gtk refactorings and improvements from Namhyung Kim * NULL deref fix for perf script, from Namhyung Kim * Assorted cleanups from Robert Richter * Let O= makes handle relative paths, from Steven Rostedt * perf script python fixes, from Feng Tang. * Improve 'perf lock' error message when the needed tracepoints are not present, from David Ahern. * Initial bash completion support, from Frederic Weisbecker * Allow building without libelf, from Namhyung Kim. * Support DWARF CFI based unwind to have callchains when %bp based unwinding is not possible, from Jiri Olsa. * Symbol resolution fixes, while fixing support PPC64 files with an .opt ELF section was the end goal, several fixes for code that handles all architectures and cleanups are included, from Cody Schafer. * Add a description for the JIT interface, from Andi Kleen. * Assorted fixes for Documentation and build in 32 bit, from Robert Richter * Add support for non-tracepoint events in perf script python, from Feng Tang * Cache the libtraceevent event_format associated to each evsel early, so that we avoid relookups, i.e. calling pevent_find_event repeatedly when processing tracepoint events. [ This is to reduce the surface contact with libtraceevents and make clear what is that the perf tools needs from that lib: so far parsing the common and per event fields. ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/pwm/pwm-lpc32xx.c')
-rw-r--r--drivers/pwm/pwm-lpc32xx.c148
1 files changed, 148 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-lpc32xx.c b/drivers/pwm/pwm-lpc32xx.c
new file mode 100644
index 00000000000..adb87f0c163
--- /dev/null
+++ b/drivers/pwm/pwm-lpc32xx.c
@@ -0,0 +1,148 @@
+/*
+ * Copyright 2012 Alexandre Pereira da Silva <aletes.xgr@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+
+struct lpc32xx_pwm_chip {
+ struct pwm_chip chip;
+ struct clk *clk;
+ void __iomem *base;
+};
+
+#define PWM_ENABLE (1 << 31)
+#define PWM_RELOADV(x) (((x) & 0xFF) << 8)
+#define PWM_DUTY(x) ((x) & 0xFF)
+
+#define to_lpc32xx_pwm_chip(_chip) \
+ container_of(_chip, struct lpc32xx_pwm_chip, chip)
+
+static int lpc32xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns)
+{
+ struct lpc32xx_pwm_chip *lpc32xx = to_lpc32xx_pwm_chip(chip);
+ unsigned long long c;
+ int period_cycles, duty_cycles;
+
+ c = clk_get_rate(lpc32xx->clk) / 256;
+ c = c * period_ns;
+ do_div(c, NSEC_PER_SEC);
+
+ /* Handle high and low extremes */
+ if (c == 0)
+ c = 1;
+ if (c > 255)
+ c = 0; /* 0 set division by 256 */
+ period_cycles = c;
+
+ c = 256 * duty_ns;
+ do_div(c, period_ns);
+ duty_cycles = c;
+
+ writel(PWM_ENABLE | PWM_RELOADV(period_cycles) | PWM_DUTY(duty_cycles),
+ lpc32xx->base + (pwm->hwpwm << 2));
+
+ return 0;
+}
+
+static int lpc32xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct lpc32xx_pwm_chip *lpc32xx = to_lpc32xx_pwm_chip(chip);
+
+ return clk_enable(lpc32xx->clk);
+}
+
+static void lpc32xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct lpc32xx_pwm_chip *lpc32xx = to_lpc32xx_pwm_chip(chip);
+
+ writel(0, lpc32xx->base + (pwm->hwpwm << 2));
+ clk_disable(lpc32xx->clk);
+}
+
+static const struct pwm_ops lpc32xx_pwm_ops = {
+ .config = lpc32xx_pwm_config,
+ .enable = lpc32xx_pwm_enable,
+ .disable = lpc32xx_pwm_disable,
+ .owner = THIS_MODULE,
+};
+
+static int lpc32xx_pwm_probe(struct platform_device *pdev)
+{
+ struct lpc32xx_pwm_chip *lpc32xx;
+ struct resource *res;
+ int ret;
+
+ lpc32xx = devm_kzalloc(&pdev->dev, sizeof(*lpc32xx), GFP_KERNEL);
+ if (!lpc32xx)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
+
+ lpc32xx->base = devm_request_and_ioremap(&pdev->dev, res);
+ if (!lpc32xx->base)
+ return -EADDRNOTAVAIL;
+
+ lpc32xx->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(lpc32xx->clk))
+ return PTR_ERR(lpc32xx->clk);
+
+ lpc32xx->chip.dev = &pdev->dev;
+ lpc32xx->chip.ops = &lpc32xx_pwm_ops;
+ lpc32xx->chip.npwm = 2;
+
+ ret = pwmchip_add(&lpc32xx->chip);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to add PWM chip, error %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, lpc32xx);
+
+ return 0;
+}
+
+static int __devexit lpc32xx_pwm_remove(struct platform_device *pdev)
+{
+ struct lpc32xx_pwm_chip *lpc32xx = platform_get_drvdata(pdev);
+
+ clk_disable(lpc32xx->clk);
+ return pwmchip_remove(&lpc32xx->chip);
+}
+
+static struct of_device_id lpc32xx_pwm_dt_ids[] = {
+ { .compatible = "nxp,lpc3220-pwm", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, lpc32xx_pwm_dt_ids);
+
+static struct platform_driver lpc32xx_pwm_driver = {
+ .driver = {
+ .name = "lpc32xx-pwm",
+ .of_match_table = of_match_ptr(lpc32xx_pwm_dt_ids),
+ },
+ .probe = lpc32xx_pwm_probe,
+ .remove = __devexit_p(lpc32xx_pwm_remove),
+};
+module_platform_driver(lpc32xx_pwm_driver);
+
+MODULE_ALIAS("platform:lpc32xx-pwm");
+MODULE_AUTHOR("Alexandre Pereira da Silva <aletes.xgr@gmail.com>");
+MODULE_DESCRIPTION("LPC32XX PWM Driver");
+MODULE_LICENSE("GPL v2");