From mboxrd@z Thu Jan  1 00:00:00 1970
From: Varka Bhadram <varkabhadram@gmail.com>
Subject: Re: [PATCH v3 2/3] rc: Introduce hix5hd2 IR transmitter driver
Date: Fri, 29 Aug 2014 09:11:41 +0530
Message-ID: <53FFF675.7020702@gmail.com>
References: <1409238977-19444-1-git-send-email-zhangfei.gao@linaro.org> <1409238977-19444-3-git-send-email-zhangfei.gao@linaro.org>
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To: Zhangfei Gao <zhangfei.gao@linaro.org>, Mauro Carvalho Chehab <m.chehab@samsung.com>, sean@mess.org, arnd@arndb.de, haifeng.yan@linaro.org, jchxue@gmail.com
Cc: linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, Guoxiong Yan <yanguoxiong@huawei.com>
List-Id: devicetree@vger.kernel.org

On 08/28/2014 08:46 PM, Zhangfei Gao wrote:
> From: Guoxiong Yan <yanguoxiong@huawei.com>
>
> IR transmitter driver for Hisilicon hix5hd2 soc
>
> By default all protocols are disabled.
> For example nec decoder can be enabled by either
> 1. ir-keytable -p nec
> 2. echo nec > /sys/class/rc/rc0/protocols
> See see Documentation/ABI/testing/sysfs-class-rc
>
(...)

> +static irqreturn_t hix5hd2_ir_rx_interrupt(int irq, void *data)
> +{
> +	u32 symb_num, symb_val, symb_time;
> +	u32 data_l, data_h;
> +	u32 irq_sr, i;
> +	struct hix5hd2_ir_priv *priv = data;
> +
> +	irq_sr = readl_relaxed(priv->base + IR_INTS);
> +	if (irq_sr & INTMS_OVERFLOW) {
> +		/*
> +		 * we must read IR_DATAL first, then we can clean up
> +		 * IR_INTS availably since logic would not clear
> +		 * fifo when overflow, drv do the job
> +		 */
> +		ir_raw_event_reset(priv->rdev);
> +		symb_num = readl_relaxed(priv->base + IR_DATAH);
> +		for (i = 0; i < symb_num; i++)
> +			readl_relaxed(priv->base + IR_DATAL);
> +
> +		writel_relaxed(INT_CLR_OVERFLOW, priv->base + IR_INTC);
> +		dev_info(priv->dev, "overflow, level=%d\n",
> +			 IR_CFG_INT_THRESHOLD);
> +	}
> +
> +	if ((irq_sr & INTMS_SYMBRCV) || (irq_sr & INTMS_TIMEOUT)) {
> +		DEFINE_IR_RAW_EVENT(ev);
> +
> +		symb_num = readl_relaxed(priv->base + IR_DATAH);
> +		for (i = 0; i < symb_num; i++) {
> +			symb_val = readl_relaxed(priv->base + IR_DATAL);
> +			data_l = ((symb_val & 0xffff) * 10);
> +			data_h =  ((symb_val >> 16) & 0xffff) * 10;
> +			symb_time = (data_l + data_h) / 10;
> +
> +			ev.duration = US_TO_NS(data_l);
> +			ev.pulse = true;
> +			ir_raw_event_store(priv->rdev, &ev);
> +
> +			if (symb_time < IR_CFG_SYMBOL_MAXWIDTH) {
> +				ev.duration = US_TO_NS(data_h);
> +				ev.pulse = false;
> +				ir_raw_event_store(priv->rdev, &ev);
> +			} else {
> +				hix5hd2_ir_send_lirc_timeout(priv->rdev);
> +			}
> +		}
> +
> +		if (irq_sr & INTMS_SYMBRCV)
> +			writel_relaxed(INT_CLR_RCV, priv->base + IR_INTC);
> +		if (irq_sr & INTMS_TIMEOUT)
> +			writel_relaxed(INT_CLR_TIMEOUT, priv->base + IR_INTC);
> +	}
> +
> +	/* Empty software fifo */
> +	ir_raw_event_handle(priv->rdev);
> +	return IRQ_HANDLED;
> +}
> +

It looks good if the entire ISR() above the probe()/remove() functionalities
of the driver. Maximum of the developers follows this structure.

(...)

> +static struct of_device_id hix5hd2_ir_table[] = {
> +	{ .compatible = "hisilicon,hix5hd2-ir", },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, hix5hd2_ir_table);
> +

Every driver put these device ids above *struct platform_driver* definition.
So that we can see the of_match_table....

> +static int hix5hd2_ir_probe(struct platform_device *pdev)
> +{
> +	int ret;
> +	struct rc_dev *rdev;
> +	struct device *dev = &pdev->dev;
> +	struct resource *res;
> +	struct hix5hd2_ir_priv *priv;
> +	struct device_node *node = pdev->dev.of_node;
> +
> +	priv = devm_kzalloc(dev, sizeof(struct hix5hd2_ir_priv), GFP_KERNEL);

sizeof(*priv)...?

> +	if (!priv)
> +		return -ENOMEM;
> +

(...)

> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(hix5hd2_ir_pm_ops, hix5hd2_ir_suspend,
> +			 hix5hd2_ir_resume);
> +

We can move the device ids here....

> +static struct platform_driver hix5hd2_ir_driver = {
> +	.driver = {
> +		.name = IR_HIX5HD2_NAME,
> +		.of_match_table = hix5hd2_ir_table,
> +		.pm     = &hix5hd2_ir_pm_ops,
> +	},
> +	.probe = hix5hd2_ir_probe,
> +	.remove = hix5hd2_ir_remove,
> +};
> +
> +module_platform_driver(hix5hd2_ir_driver);
> +
> +MODULE_DESCRIPTION("RC Transceiver driver for hix5hd2 platforms");
> +MODULE_AUTHOR("Guoxiong Yan <yanguoxiong@huawei.com>");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:hix5hd2-ir");


-- 
Regards,
Varka Bhadram.