On Mon, 2010-07-12 at 13:56 -0700, Kevin McNeely wrote:

below it's named cyttsp-i2c

To quote Dmitry Torokhov:
"No file names  (and especially paths) in comment blocks please - makes
harder to move stuff around."

+ *
+ * Copyright (C) 2009, 2010 Cypress Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2, and only version 2, as published by the
+ * Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Cypress reserves the right to make changes without further notice
+ * to the materials described herein. Cypress does not assume any
+ * liability arising out of the application described herein.

Sure, Cypress can engineer what they want. The warranty is already
covered by GPL.

+ *
+ * Contact Cypress Semiconductor at www.cypress.com

Maintainer or at least a email ad would be nice I think.

+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/timer.h>
+#include <linux/workqueue.h>
+#include <linux/byteorder/generic.h>
+#include <linux/bitops.h>
+#ifdef CONFIG_HAS_EARLYSUSPEND
+#include <linux/earlysuspend.h>
+#endif /* CONFIG_HAS_EARLYSUSPEND */
+
+#define CY_DECLARE_GLOBALS
+
+#include <linux/cyttsp.h>

Would it be possible to move cyttsp.h to the local folder?

+
+uint32_t cyttsp_tsdebug1 = 0xff;

why can't this be static?
why is it in the header too?

+module_param_named(tsdebug1, cyttsp_tsdebug1, uint, 0664);
+
+/* CY TTSP I2C Driver private data */
+struct cyttsp {
+	struct i2c_client *client;
+	struct input_dev *input;
+	struct work_struct work;
+	struct timer_list timer;
+	struct mutex mutex;
+	char phys[32];
+	struct cyttsp_platform_data *platform_data;
+	u8 num_prv_st_tch;
+	u16 act_trk[CY_NUM_TRK_ID];
+	u16 prv_st_tch[CY_NUM_ST_TCH_ID];
+	u16 prv_mt_tch[CY_NUM_MT_TCH_ID];
+	u16 prv_mt_pos[CY_NUM_TRK_ID][2];
+	atomic_t irq_enabled;
+#ifdef CONFIG_HAS_EARLYSUSPEND
+	struct early_suspend early_suspend;
+#endif /* CONFIG_HAS_EARLYSUSPEND */
+};
+static u8 irq_cnt;		/* comparison counter with register valuw */
+static u32 irq_cnt_total;	/* total interrupts */
+static u32 irq_err_cnt;		/* count number of touch interrupts with err */
+#define CY_IRQ_CNT_MASK	0x000000FF	/* mapped for sizeof count in reg */
+#define CY_IRQ_CNT_REG	0x00		/* tt_undef[0]=reg 0x1B - Gen3 only */
+
+#ifdef CONFIG_HAS_EARLYSUSPEND
+static void cyttsp_early_suspend(struct early_suspend *handler);
+static void cyttsp_late_resume(struct early_suspend *handler);
+#endif /* CONFIG_HAS_EARLYSUSPEND */
+
+static struct workqueue_struct *cyttsp_ts_wq;
+
+
+/* ****************************************************************************
+ * Prototypes for static functions
+ * ************************************************************************** */

star gap, and more than 80 chars

+static void cyttsp_xy_worker(struct work_struct *work);
+static irqreturn_t cyttsp_irq(int irq, void *handle);
+static int cyttsp_inlist(u16 prev_track[],
+			u8 cur_trk_id, u8 *prev_loc, u8 num_touches);
+static int cyttsp_next_avail_inlist(u16 cur_trk[],
+			u8 *new_loc, u8 num_touches);
+static int cyttsp_putbl(struct cyttsp *ts, int show,
+			int show_status, int show_version, int show_cid);
+static int __devinit cyttsp_probe(struct i2c_client *client,
+			const struct i2c_device_id *id);
+static int __devexit cyttsp_remove(struct i2c_client *client);
+static int cyttsp_resume(struct i2c_client *client);
+static int cyttsp_suspend(struct i2c_client *client, pm_message_t message);

could these prototypes be avoided?

+
+/* Static variables */
+static struct cyttsp_gen3_xydata_t g_xy_data;
+static struct cyttsp_bootloader_data_t g_bl_data;
+static struct cyttsp_sysinfo_data_t g_sysinfo_data;
+static const struct i2c_device_id cyttsp_id[] = {
+	{ CY_I2C_NAME, 0 },  { }
+};
+static u8 bl_cmd[] = {
+	CY_BL_FILE0, CY_BL_CMD, CY_BL_EXIT,
+	CY_BL_KEY0, CY_BL_KEY1, CY_BL_KEY2,
+	CY_BL_KEY3, CY_BL_KEY4, CY_BL_KEY5,
+	CY_BL_KEY6, CY_BL_KEY7};
+
+MODULE_DEVICE_TABLE(i2c, cyttsp_id);
+
+static struct i2c_driver cyttsp_driver = {
+	.driver = {
+		.name = CY_I2C_NAME,
+		.owner = THIS_MODULE,
+	},
+	.probe = cyttsp_probe,
+	.remove = __devexit_p(cyttsp_remove),
+	.suspend = cyttsp_suspend,
+	.resume = cyttsp_resume,
+	.id_table = cyttsp_id,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard touchscreen driver");
+MODULE_AUTHOR("Cypress");

Why not re-factoring the whole driver to keep consistency with other
touchpad drivers?
A maintainer to contact or at least a email-ad would be nice I think.
You could use scripts/checkpatch.pl to find some warnings.

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