| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <19977.44219.214485.118656@ipc1.ka-ro>
Date: Tue, 28 Jun 2011 12:28:11 +0200
From: Lothar Waßmann <LW@...O-electronics.de>
To: Sascha Hauer <s.hauer@...gutronix.de>
Cc: linux-kernel@...r.kernel.org, Arnd Bergmann <arnd@...db.de>,
Ryan Mallon <ryan@...ewatersys.com>,
Shawn Guo <shawn.guo@...aro.org>,
linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH 2/2] pwm: Add a i.MX23/28 pwm driver
Hi,
just some nitpicks...
Sascha Hauer writes:
> Signed-off-by: Sascha Hauer <s.hauer@...gutronix.de>
> ---
> drivers/pwm/mxs-pwm.c | 275 +++++++++++++++++++++++++++++++++++++++++++++++++
> 1 files changed, 275 insertions(+), 0 deletions(-)
> create mode 100644 drivers/pwm/mxs-pwm.c
>
> diff --git a/drivers/pwm/mxs-pwm.c b/drivers/pwm/mxs-pwm.c
> new file mode 100644
> index 0000000..052cb0c
> --- /dev/null
> +++ b/drivers/pwm/mxs-pwm.c
> @@ -0,0 +1,275 @@
> +/*
> + * Copyright (C) 2011 Pengutronix
> + * Sascha Hauer <s.hauer@...gutronix.de>
> + *
> + * simple driver for PWM (Pulse Width Modulator) controller
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * Derived from pxa PWM driver by eric miao <eric.miao@...vell.com>
> + */
> +
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/err.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/io.h>
> +#include <linux/pwm.h>
> +#include <mach/hardware.h>
> +#include <mach/mxs.h>
> +#include <mach/mx23.h>
> +#include <mach/mx28.h>
> +#include <asm/div64.h>
> +
> +struct mxs_pwm_device {
> + struct device *dev;
> +
> + struct clk *clk;
> +
> + int enabled;
> + void __iomem *mmio_base;
> +
> + unsigned int pwm_id;
> +
> + u32 val_active;
> + u32 val_period;
> + int period_us;
> + struct pwm_chip chip;
> +};
> +
> +/* common register space */
> +static void __iomem *pwm_base_common;
> +#define REG_PWM_CTRL 0x0
> +#define PWM_SFTRST (1 << 31)
> +#define PWM_CLKGATE (1 << 30)
> +#define PWM_ENABLE(p) (1 << (p))
> +
> +/* per pwm register space */
> +#define REG_ACTIVE 0x0
> +#define REG_PERIOD 0x10
> +
> +#define PERIOD_PERIOD(p) ((p) & 0xffff)
> +#define PERIOD_ACTIVE_HIGH (3 << 16)
> +#define PERIOD_INACTIVE_LOW (2 << 18)
> +#define PERIOD_CDIV(div) (((div) & 0x7) << 20)
> +
[...]
> +static int __devinit mxs_pwm_probe(struct platform_device *pdev)
> +{
> + struct mxs_pwm_device *pwm;
> + struct resource *r;
> + int ret = 0;
> +
> + pwm = devm_kzalloc(&pdev->dev, sizeof(struct mxs_pwm_device), GFP_KERNEL);
> + if (pwm == NULL) {
> + dev_err(&pdev->dev, "failed to allocate memory\n");
> + return -ENOMEM;
> + }
> +
> + pwm->clk = clk_get(&pdev->dev, NULL);
> +
> + if (IS_ERR(pwm->clk)) {
Why an empty line here, but not in other similar places?
> + ret = PTR_ERR(pwm->clk);
> + goto err_free;
> + }
> +
> + pwm->chip.ops = &mxs_pwm_ops;
> +
> + pwm->enabled = 0;
is already 0 due to kzalloc().
> +
> + pwm->chip.pwm_id = pdev->id;
> + pwm->chip.owner = THIS_MODULE;
> +
> + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (r == NULL) {
> + dev_err(&pdev->dev, "no memory resource defined\n");
> + ret = -ENODEV;
> + goto err_free_clk;
> + }
> +
> + r = request_mem_region(r->start, resource_size(r), pdev->name);
> + if (r == NULL) {
> + dev_err(&pdev->dev, "failed to request memory resource\n");
> + ret = -EBUSY;
> + goto err_free_clk;
> + }
> +
> + pwm->mmio_base = ioremap(r->start, resource_size(r));
> + if (pwm->mmio_base == NULL) {
> + dev_err(&pdev->dev, "failed to ioremap() registers\n");
> + ret = -ENODEV;
-ENOMEM?.
> + if (ret)
> + goto err_free_mem;
> +
> + platform_set_drvdata(pdev, pwm);
> + return 0;
> +
> +err_free_mem:
> + release_mem_region(r->start, resource_size(r));
> +err_free_clk:
> + clk_put(pwm->clk);
> +err_free:
> + kfree(pwm);
> + return ret;
> +}
> +
> +static int __devexit mxs_pwm_remove(struct platform_device *pdev)
> +{
> + struct mxs_pwm_device *pwm;
> + struct resource *r;
> + int ret;
> +
> + pwm = platform_get_drvdata(pdev);
> +
> + ret = pwmchip_remove(&pwm->chip);
> + if (ret)
> + return ret;
> +
> + iounmap(pwm->mmio_base);
> +
> + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + release_mem_region(r->start, resource_size(r));
> +
> + clk_put(pwm->clk);
> +
> + return 0;
> +}
> +
> +static struct platform_driver mxs_pwm_driver = {
> + .driver = {
> + .name = "mxs-pwm",
> + },
> + .probe = mxs_pwm_probe,
> + .remove = __devexit_p(mxs_pwm_remove),
> +};
> +
> +static int __init mxs_pwm_init(void)
> +{
> + if (cpu_is_mx28())
> + pwm_base_common = MX28_IO_ADDRESS(MX28_PWM_BASE_ADDR);
> + else
> + pwm_base_common = MX23_IO_ADDRESS(MX23_PWM_BASE_ADDR);
> +
> + __mxs_clrl(PWM_SFTRST | PWM_CLKGATE, pwm_base_common + REG_PWM_CTRL);
> +
Shouldn't CLKGATE be set again in the remove() function?
Lothar Waßmann
--
___________________________________________________________
Ka-Ro electronics GmbH | Pascalstraße 22 | D - 52076 Aachen
Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10
Geschäftsführer: Matthias Kaussen
Handelsregistereintrag: Amtsgericht Aachen, HRB 4996
www.karo-electronics.de | info@...o-electronics.de
___________________________________________________________
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists