1 files changed, 66 insertions, 212 deletions

diff --git a/drivers/auxdisplay/img-ascii-lcd.c b/drivers/auxdisplay/img-ascii-lcd.c
index 25306fa27251..32e1863ef4b2 100644
--- a/drivers/auxdisplay/img-ascii-lcd.c
+++ b/drivers/auxdisplay/img-ascii-lcd.c
@@ -1,24 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (C) 2016 Imagination Technologies
- * Author: Paul Burton <paul.burton@imgtec.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; either version 2 of the License, or (at your
- * option) any later version.
+ * Author: Paul Burton <paul.burton@mips.com>
  */
 
-#include <generated/utsrelease.h>
 #include <linux/kernel.h>
 #include <linux/io.h>
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
-#include <linux/of_address.h>
-#include <linux/of_platform.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 #include <linux/regmap.h>
 #include <linux/slab.h>
-#include <linux/sysfs.h>
+
+#include "line-display.h"
 
 struct img_ascii_lcd_ctx;
 
@@ -26,82 +22,74 @@ struct img_ascii_lcd_ctx;
  * struct img_ascii_lcd_config - Configuration information about an LCD model
  * @num_chars: the number of characters the LCD can display
  * @external_regmap: true if registers are in a system controller, else false
- * @update: function called to update the LCD
+ * @ops: character line display operations
  */
 struct img_ascii_lcd_config {
 	unsigned int num_chars;
 	bool external_regmap;
-	void (*update)(struct img_ascii_lcd_ctx *ctx);
+	const struct linedisp_ops ops;
 };
 
 /**
  * struct img_ascii_lcd_ctx - Private data structure
- * @pdev: the ASCII LCD platform device
+ * @linedisp: line display structure
  * @base: the base address of the LCD registers
  * @regmap: the regmap through which LCD registers are accessed
  * @offset: the offset within regmap to the start of the LCD registers
- * @cfg: pointer to the LCD model configuration
- * @message: the full message to display or scroll on the LCD
- * @message_len: the length of the @message string
- * @scroll_pos: index of the first character of @message currently displayed
- * @scroll_rate: scroll interval in jiffies
- * @timer: timer used to implement scrolling
- * @curr: the string currently displayed on the LCD
  */
 struct img_ascii_lcd_ctx {
-	struct platform_device *pdev;
+	struct linedisp linedisp;
 	union {
 		void __iomem *base;
 		struct regmap *regmap;
 	};
 	u32 offset;
-	const struct img_ascii_lcd_config *cfg;
-	char *message;
-	unsigned int message_len;
-	unsigned int scroll_pos;
-	unsigned int scroll_rate;
-	struct timer_list timer;
-	char curr[] __aligned(8);
 };
 
 /*
  * MIPS Boston development board
  */
 
-static void boston_update(struct img_ascii_lcd_ctx *ctx)
+static void boston_update(struct linedisp *linedisp)
 {
+	struct img_ascii_lcd_ctx *ctx =
+		container_of(linedisp, struct img_ascii_lcd_ctx, linedisp);
 	ulong val;
 
 #if BITS_PER_LONG == 64
-	val = *((u64 *)&ctx->curr[0]);
+	val = *((u64 *)&linedisp->buf[0]);
 	__raw_writeq(val, ctx->base);
 #elif BITS_PER_LONG == 32
-	val = *((u32 *)&ctx->curr[0]);
+	val = *((u32 *)&linedisp->buf[0]);
 	__raw_writel(val, ctx->base);
-	val = *((u32 *)&ctx->curr[4]);
+	val = *((u32 *)&linedisp->buf[4]);
 	__raw_writel(val, ctx->base + 4);
 #else
 # error Not 32 or 64 bit
 #endif
 }
 
-static struct img_ascii_lcd_config boston_config = {
+static const struct img_ascii_lcd_config boston_config = {
 	.num_chars = 8,
-	.update = boston_update,
+	.ops = {
+		.update = boston_update,
+	},
 };
 
 /*
  * MIPS Malta development board
  */
 
-static void malta_update(struct img_ascii_lcd_ctx *ctx)
+static void malta_update(struct linedisp *linedisp)
 {
+	struct img_ascii_lcd_ctx *ctx =
+		container_of(linedisp, struct img_ascii_lcd_ctx, linedisp);
 	unsigned int i;
-	int err;
+	int err = 0;
 
-	for (i = 0; i < ctx->cfg->num_chars; i++) {
+	for (i = 0; i < linedisp->num_chars; i++) {
 		err = regmap_write(ctx->regmap,
-				   ctx->offset + (i * 8), ctx->curr[i]);
+				   ctx->offset + (i * 8), linedisp->buf[i]);
 		if (err)
 			break;
 	}
@@ -110,10 +98,12 @@ static void malta_update(struct img_ascii_lcd_ctx *ctx)
 		pr_err_ratelimited("Failed to update LCD display: %d\n", err);
 }
 
-static struct img_ascii_lcd_config malta_config = {
+static const struct img_ascii_lcd_config malta_config = {
 	.num_chars = 8,
 	.external_regmap = true,
-	.update = malta_update,
+	.ops = {
+		.update = malta_update,
+	},
 };
 
 /*
@@ -177,12 +167,14 @@ static int sead3_wait_lcd_idle(struct img_ascii_lcd_ctx *ctx)
 	return 0;
 }
 
-static void sead3_update(struct img_ascii_lcd_ctx *ctx)
+static void sead3_update(struct linedisp *linedisp)
 {
+	struct img_ascii_lcd_ctx *ctx =
+		container_of(linedisp, struct img_ascii_lcd_ctx, linedisp);
 	unsigned int i;
-	int err;
+	int err = 0;
 
-	for (i = 0; i < ctx->cfg->num_chars; i++) {
+	for (i = 0; i < linedisp->num_chars; i++) {
 		err = sead3_wait_lcd_idle(ctx);
 		if (err)
 			break;
@@ -199,7 +191,7 @@ static void sead3_update(struct img_ascii_lcd_ctx *ctx)
 
 		err = regmap_write(ctx->regmap,
 				   ctx->offset + SEAD3_REG_LCD_DATA,
-				   ctx->curr[i]);
+				   linedisp->buf[i]);
 		if (err)
 			break;
 	}
@@ -208,10 +200,12 @@ static void sead3_update(struct img_ascii_lcd_ctx *ctx)
 		pr_err_ratelimited("Failed to update LCD display: %d\n", err);
 }
 
-static struct img_ascii_lcd_config sead3_config = {
+static const struct img_ascii_lcd_config sead3_config = {
 	.num_chars = 16,
 	.external_regmap = true,
-	.update = sead3_update,
+	.ops = {
+		.update = sead3_update,
+	},
 };
 
 static const struct of_device_id img_ascii_lcd_matches[] = {
@@ -223,130 +217,6 @@ static const struct of_device_id img_ascii_lcd_matches[] = {
 MODULE_DEVICE_TABLE(of, img_ascii_lcd_matches);
 
 /**
- * img_ascii_lcd_scroll() - scroll the display by a character
- * @arg: really a pointer to the private data structure
- *
- * Scroll the current message along the LCD by one character, rearming the
- * timer if required.
- */
-static void img_ascii_lcd_scroll(unsigned long arg)
-{
-	struct img_ascii_lcd_ctx *ctx = (struct img_ascii_lcd_ctx *)arg;
-	unsigned int i, ch = ctx->scroll_pos;
-	unsigned int num_chars = ctx->cfg->num_chars;
-
-	/* update the current message string */
-	for (i = 0; i < num_chars;) {
-		/* copy as many characters from the string as possible */
-		for (; i < num_chars && ch < ctx->message_len; i++, ch++)
-			ctx->curr[i] = ctx->message[ch];
-
-		/* wrap around to the start of the string */
-		ch = 0;
-	}
-
-	/* update the LCD */
-	ctx->cfg->update(ctx);
-
-	/* move on to the next character */
-	ctx->scroll_pos++;
-	ctx->scroll_pos %= ctx->message_len;
-
-	/* rearm the timer */
-	if (ctx->message_len > ctx->cfg->num_chars)
-		mod_timer(&ctx->timer, jiffies + ctx->scroll_rate);
-}
-
-/**
- * img_ascii_lcd_display() - set the message to be displayed
- * @ctx: pointer to the private data structure
- * @msg: the message to display
- * @count: length of msg, or -1
- *
- * Display a new message @msg on the LCD. @msg can be longer than the number of
- * characters the LCD can display, in which case it will begin scrolling across
- * the LCD display.
- *
- * Return: 0 on success, -ENOMEM on memory allocation failure
- */
-static int img_ascii_lcd_display(struct img_ascii_lcd_ctx *ctx,
-			     const char *msg, ssize_t count)
-{
-	char *new_msg;
-
-	/* stop the scroll timer */
-	del_timer_sync(&ctx->timer);
-
-	if (count == -1)
-		count = strlen(msg);
-
-	/* if the string ends with a newline, trim it */
-	if (msg[count - 1] == '\n')
-		count--;
-
-	new_msg = devm_kmalloc(&ctx->pdev->dev, count + 1, GFP_KERNEL);
-	if (!new_msg)
-		return -ENOMEM;
-
-	memcpy(new_msg, msg, count);
-	new_msg[count] = 0;
-
-	if (ctx->message)
-		devm_kfree(&ctx->pdev->dev, ctx->message);
-
-	ctx->message = new_msg;
-	ctx->message_len = count;
-	ctx->scroll_pos = 0;
-
-	/* update the LCD */
-	img_ascii_lcd_scroll((unsigned long)ctx);
-
-	return 0;
-}
-
-/**
- * message_show() - read message via sysfs
- * @dev: the LCD device
- * @attr: the LCD message attribute
- * @buf: the buffer to read the message into
- *
- * Read the current message being displayed or scrolled across the LCD display
- * into @buf, for reads from sysfs.
- *
- * Return: the number of characters written to @buf
- */
-static ssize_t message_show(struct device *dev, struct device_attribute *attr,
-			    char *buf)
-{
-	struct img_ascii_lcd_ctx *ctx = dev_get_drvdata(dev);
-
-	return sprintf(buf, "%s\n", ctx->message);
-}
-
-/**
- * message_store() - write a new message via sysfs
- * @dev: the LCD device
- * @attr: the LCD message attribute
- * @buf: the buffer containing the new message
- * @count: the size of the message in @buf
- *
- * Write a new message to display or scroll across the LCD display from sysfs.
- *
- * Return: the size of the message on success, else -ERRNO
- */
-static ssize_t message_store(struct device *dev, struct device_attribute *attr,
-			     const char *buf, size_t count)
-{
-	struct img_ascii_lcd_ctx *ctx = dev_get_drvdata(dev);
-	int err;
-
-	err = img_ascii_lcd_display(ctx, buf, count);
-	return err ?: count;
-}
-
-static DEVICE_ATTR_RW(message);
-
-/**
  * img_ascii_lcd_probe() - probe an LCD display device
  * @pdev: the LCD platform device
  *
@@ -357,62 +227,44 @@ static DEVICE_ATTR_RW(message);
  */
 static int img_ascii_lcd_probe(struct platform_device *pdev)
 {
-	const struct of_device_id *match;
-	const struct img_ascii_lcd_config *cfg;
+	struct device *dev = &pdev->dev;
+	const struct img_ascii_lcd_config *cfg = device_get_match_data(dev);
 	struct img_ascii_lcd_ctx *ctx;
-	struct resource *res;
 	int err;
 
-	match = of_match_device(img_ascii_lcd_matches, &pdev->dev);
-	if (!match)
-		return -ENODEV;
-
-	cfg = match->data;
-	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx) + cfg->num_chars,
-			   GFP_KERNEL);
+	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
 	if (!ctx)
 		return -ENOMEM;
 
 	if (cfg->external_regmap) {
-		ctx->regmap = syscon_node_to_regmap(pdev->dev.parent->of_node);
+		ctx->regmap = syscon_node_to_regmap(dev->parent->of_node);
 		if (IS_ERR(ctx->regmap))
 			return PTR_ERR(ctx->regmap);
 
-		if (of_property_read_u32(pdev->dev.of_node, "offset",
-					 &ctx->offset))
+		if (of_property_read_u32(dev->of_node, "offset", &ctx->offset))
 			return -EINVAL;
 	} else {
-		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-		ctx->base = devm_ioremap_resource(&pdev->dev, res);
+		ctx->base = devm_platform_ioremap_resource(pdev, 0);
 		if (IS_ERR(ctx->base))
 			return PTR_ERR(ctx->base);
 	}
 
-	ctx->pdev = pdev;
-	ctx->cfg = cfg;
-	ctx->message = NULL;
-	ctx->scroll_pos = 0;
-	ctx->scroll_rate = HZ / 2;
-
-	/* initialise a timer for scrolling the message */
-	init_timer(&ctx->timer);
-	ctx->timer.function = img_ascii_lcd_scroll;
-	ctx->timer.data = (unsigned long)ctx;
-
-	platform_set_drvdata(pdev, ctx);
-
-	/* display a default message */
-	err = img_ascii_lcd_display(ctx, "Linux " UTS_RELEASE "       ", -1);
+	err = linedisp_register(&ctx->linedisp, dev, cfg->num_chars, &cfg->ops);
 	if (err)
-		goto out_del_timer;
+		return err;
 
-	err = device_create_file(&pdev->dev, &dev_attr_message);
+	/* for backwards compatibility */
+	err = compat_only_sysfs_link_entry_to_kobj(&dev->kobj,
+						   &ctx->linedisp.dev.kobj,
+						   "message", NULL);
 	if (err)
-		goto out_del_timer;
+		goto err_unregister;
 
+	platform_set_drvdata(pdev, ctx);
 	return 0;
-out_del_timer:
-	del_timer_sync(&ctx->timer);
+
+err_unregister:
+	linedisp_unregister(&ctx->linedisp);
 	return err;
 }
 
@@ -422,16 +274,13 @@ out_del_timer:
  *
  * Remove an LCD display device, freeing private resources & ensuring that the
  * driver stops using the LCD display registers.
- *
- * Return: 0
  */
-static int img_ascii_lcd_remove(struct platform_device *pdev)
+static void img_ascii_lcd_remove(struct platform_device *pdev)
 {
 	struct img_ascii_lcd_ctx *ctx = platform_get_drvdata(pdev);
 
-	device_remove_file(&pdev->dev, &dev_attr_message);
-	del_timer_sync(&ctx->timer);
-	return 0;
+	sysfs_remove_link(&pdev->dev.kobj, "message");
+	linedisp_unregister(&ctx->linedisp);
 }
 
 static struct platform_driver img_ascii_lcd_driver = {
@@ -440,6 +289,11 @@ static struct platform_driver img_ascii_lcd_driver = {
 		.of_match_table	= img_ascii_lcd_matches,
 	},
 	.probe	= img_ascii_lcd_probe,
-	.remove	= img_ascii_lcd_remove,
+	.remove = img_ascii_lcd_remove,
 };
 module_platform_driver(img_ascii_lcd_driver);
+
+MODULE_DESCRIPTION("Imagination Technologies ASCII LCD Display");
+MODULE_AUTHOR("Paul Burton <paul.burton@mips.com>");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("LINEDISP");