Re: [PATCH v5 2/6] HID: Add Himax HX83102J touchscreen driver

+/**
+ * himax_spi_drv_probe - Probe function for the SPI driver
+ * @spi: Pointer to the spi_device structure
+ *
+ * This function is called when the SPI driver is probed. It initializes the
+ * himax_ts_data structure and assign the settings from spi device to
+ * himax_ts_data. The buffer for SPI transfer is allocate here. The SPI
+ * transfer settings also setup before any communication starts.
+ *
+ * Return: 0 on success, negative error code on failure
+ */
+static int himax_spi_drv_probe(struct spi_device *spi)
+{
+	int ret;
+	struct himax_ts_data *ts;
+	static struct himax_platform_data *pdata;
+
+	dev_info(&spi->dev, "%s: Himax SPI driver probe\n", __func__);

+	ts = devm_kzalloc(&spi->dev, sizeof(struct himax_ts_data), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+	if (spi->controller->flags & SPI_CONTROLLER_HALF_DUPLEX) {
+		dev_err(ts->dev, "%s: Full duplex not supported by host\n", __func__);

+		return -EIO;
+	}
+	pdata = &ts->pdata;
+	ts->dev = &spi->dev;
+	if (!spi->irq) {
+		dev_err(ts->dev, "%s: no IRQ?\n", __func__);
+		return -EINVAL;
+	}
+	ts->himax_irq = spi->irq;
+	pdata->gpiod_rst = devm_gpiod_get(ts->dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(pdata->gpiod_rst)) {
+		dev_err(ts->dev, "%s: gpio-rst value is not valid\n", __func__);

+		return -EIO;
+	}
+
+	spi->bits_per_word = 8;
+	spi->mode = SPI_MODE_3;
+	spi->cs_setup.value = HIMAX_SPI_CS_SETUP_TIME;
+
+	ts->spi = spi;
+	/*
+	 * The max_transfer_size is used to allocate the buffer for SPI transfer.
+	 * The size should be given by the SPI master driver, but if not available
+	 * then use the HIMAX_MAX_TP_EV_STACK_SZ as default. Which is the least size for
+	 * each TP event data.
+	 */
+	if (spi->controller->max_transfer_size)
+		ts->spi_xfer_max_sz = spi->controller->max_transfer_size(spi);
+	else
+		ts->spi_xfer_max_sz = HIMAX_MAX_TP_EV_STACK_SZ;
+
+	ts->spi_xfer_max_sz = min(ts->spi_xfer_max_sz, HIMAX_BUS_RW_MAX_LEN);
+	/* SPI full-duplex rx_buf and tx_buf should be equal */
+	ts->xfer_rx_data = devm_kzalloc(ts->dev, ts->spi_xfer_max_sz, GFP_KERNEL);
+	if (!ts->xfer_rx_data)
+		return -ENOMEM;
+
+	ts->xfer_tx_data = devm_kzalloc(ts->dev, ts->spi_xfer_max_sz, GFP_KERNEL);
+	if (!ts->xfer_tx_data)
+		return -ENOMEM;
+
+	spin_lock_init(&ts->irq_lock);
+	mutex_init(&ts->rw_lock);
+	mutex_init(&ts->reg_lock);
+	dev_set_drvdata(&spi->dev, ts);
+	spi_set_drvdata(spi, ts);
+
+	ts->probe_finish = false;
+	ts->initialized = false;
+	ts->ic_boot_done = false;
+
+	ret = himax_platform_init(ts);
+	if (ret) {
+		dev_err(ts->dev, "%s: platform init failed\n", __func__);
+		return ret;
+	}
+
+	ret = himax_chip_detect(ts);
+	if (ret) {
+		dev_err(ts->dev, "%s: IC detect failed\n", __func__);
+		return ret;
+	}
+
+	ret = himax_chip_init(ts);
+	if (ret < 0)
+		return ret;
+	ts->probe_finish = true;
+
+	return ret;
+	himax_platform_deinit(ts);
+}
+
+/**
+ * himax_spi_drv_remove - Remove function for the SPI driver
+ * @spi: Pointer to the spi_device structure
+ *
+ * This function is called when the SPI driver is removed. It deinitializes the

+ * himax_ts_data structure and free the resources allocated for the SPI
+ * communication.
+ */
+static void himax_spi_drv_remove(struct spi_device *spi)
+{
+	struct himax_ts_data *ts = spi_get_drvdata(spi);
+
+	if (ts->probe_finish) {
+		if (ts->ic_boot_done) {
+			himax_int_enable(ts, false);
+
+			if (ts->hid_probed)
+				himax_hid_remove(ts);
+		}
+		himax_platform_deinit(ts);
+	}
+}
+
+/**

+ * himax_shutdown - Shutdown the touch screen
+ * @spi: Himax touch screen spi device
+ *
+ * This function is used to shutdown the touch screen. It will disable the
+ * interrupt, set the reset pin to activate state. Then remove the hid device.

+ *
+ * Return: None
+ */
+static void himax_shutdown(struct spi_device *spi)
+{
+	struct himax_ts_data *ts = spi_get_drvdata(spi);
+
+	if (!ts->initialized) {
+		dev_err(ts->dev, "%s: init not ready, skip!\n", __func__);
+		return;
+	}
+
+	himax_int_enable(ts, false);
+	gpiod_set_value(ts->pdata.gpiod_rst, 1);
+	himax_power_deconfig(&ts->pdata);
+	himax_hid_remove(ts);
+}
+
+#if defined(CONFIG_OF)

+static const struct of_device_id himax_table[] = {
+	{ .compatible = "himax,hx83102j" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, himax_table);
+#endif
+
+static struct spi_driver himax_hid_over_spi_driver = {
+	.driver = {
+		.name =		"hx83102j",
+		.owner =	THIS_MODULE,

+		.of_match_table = of_match_ptr(himax_table),
+#endif
+	},
+	.probe =	himax_spi_drv_probe,
+	.remove =	himax_spi_drv_remove,
+	.shutdown =	himax_shutdown,
+};
+
+static int __init himax_ic_init(void)
+{
+	return spi_register_driver(&himax_hid_over_spi_driver);
+}
+
+static void __exit himax_ic_exit(void)
+{
+	spi_unregister_driver(&himax_hid_over_spi_driver);
+}
+
+module_init(himax_ic_init);
+module_exit(himax_ic_exit);