[PATCH v1 08/15] auxdisplay: linedisp: Provide struct linedisp_ops for future extension

Andy Shevchenko
2024-02-08T18:49:30Z

Currently the line display library doesn't scale in case we want to
provide more operations. Prepare the library to take a newly created
struct linedisp_ops that scales.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/auxdisplay/ht16k33.c | 7 +++++--
drivers/auxdisplay/img-ascii-lcd.c | 19 ++++++++++++-------
drivers/auxdisplay/line-display.c | 11 +++++------
drivers/auxdisplay/line-display.h | 17 +++++++++++++----
4 files changed, 35 insertions(+), 19 deletions(-)

diff --git a/drivers/auxdisplay/ht16k33.c b/drivers/auxdisplay/ht16k33.c
index c6a42c5c128f..0cdf3fbdf81e 100644
--- a/drivers/auxdisplay/ht16k33.c
+++ b/drivers/auxdisplay/ht16k33.c
@@ -448,6 +448,10 @@ static void ht16k33_linedisp_update(struct linedisp *linedisp)
schedule_delayed_work(&priv->work, 0);
}

+static const struct linedisp_ops ht16k33_linedisp_ops = {
+ .update = ht16k33_linedisp_update,
+};
+
static void ht16k33_seg7_update(struct work_struct *work)
{
struct ht16k33_priv *priv = container_of(work, struct ht16k33_priv,
@@ -696,8 +700,7 @@ static int ht16k33_seg_probe(struct device *dev, struct ht16k33_priv *priv,
if (err)
return err;

- err = linedisp_register(&seg->linedisp, dev, 4, seg->curr,
- ht16k33_linedisp_update);
+ err = linedisp_register(&seg->linedisp, dev, 4, seg->curr, &ht16k33_linedisp_ops);
if (err)
goto err_remove_map_file;

diff --git a/drivers/auxdisplay/img-ascii-lcd.c b/drivers/auxdisplay/img-ascii-lcd.c
index c571e54d9eb5..c0ec7d9a1c62 100644
--- a/drivers/auxdisplay/img-ascii-lcd.c
+++ b/drivers/auxdisplay/img-ascii-lcd.c
@@ -22,12 +22,12 @@ 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 linedisp *linedisp);
+ const struct linedisp_ops ops;
};

/**
@@ -75,7 +75,9 @@ static void boston_update(struct linedisp *linedisp)

static struct img_ascii_lcd_config boston_config = {
.num_chars = 8,
- .update = boston_update,
+ .ops = {
+ .update = boston_update,
+ },
};

/*
@@ -103,7 +105,9 @@ static void malta_update(struct linedisp *linedisp)
static struct img_ascii_lcd_config malta_config = {
.num_chars = 8,
.external_regmap = true,
- .update = malta_update,
+ .ops = {
+ .update = malta_update,
+ },
};

/*
@@ -203,7 +207,9 @@ static void sead3_update(struct linedisp *linedisp)
static 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[] = {
@@ -247,8 +253,7 @@ static int img_ascii_lcd_probe(struct platform_device *pdev)
return PTR_ERR(ctx->base);
}

- err = linedisp_register(&ctx->linedisp, dev, cfg->num_chars, ctx->curr,
- cfg->update);
+ err = linedisp_register(&ctx->linedisp, dev, cfg->num_chars, ctx->curr, &cfg->ops);
if (err)
return err;

diff --git a/drivers/auxdisplay/line-display.c b/drivers/auxdisplay/line-display.c
index 851b2c0f9443..62e8a911bb12 100644
--- a/drivers/auxdisplay/line-display.c
+++ b/drivers/auxdisplay/line-display.c
@@ -50,7 +50,7 @@ static void linedisp_scroll(struct timer_list *t)
}

/* update the display */
- linedisp->update(linedisp);
+ linedisp->ops->update(linedisp);

/* move on to the next character */
linedisp->scroll_pos++;
@@ -94,7 +94,7 @@ static int linedisp_display(struct linedisp *linedisp, const char *msg,
linedisp->message = NULL;
linedisp->message_len = 0;
memset(linedisp->buf, ' ', linedisp->num_chars);
- linedisp->update(linedisp);
+ linedisp->ops->update(linedisp);
return 0;
}

@@ -216,20 +216,19 @@ static const struct device_type linedisp_type = {
* @parent: parent device
* @num_chars: the number of characters that can be displayed
* @buf: pointer to a buffer that can hold @num_chars characters
- * @update: Function called to update the display. This must not sleep!
+ * @ops: character line display operations
*
* Return: zero on success, else a negative error code.
*/
int linedisp_register(struct linedisp *linedisp, struct device *parent,
- unsigned int num_chars, char *buf,
- void (*update)(struct linedisp *linedisp))
+ unsigned int num_chars, char *buf, const struct linedisp_ops *ops)
{
int err;

memset(linedisp, 0, sizeof(*linedisp));
linedisp->dev.parent = parent;
linedisp->dev.type = &linedisp_type;
- linedisp->update = update;
+ linedisp->ops = ops;
linedisp->buf = buf;
linedisp->num_chars = num_chars;
linedisp->scroll_rate = DEFAULT_SCROLL_RATE;
diff --git a/drivers/auxdisplay/line-display.h b/drivers/auxdisplay/line-display.h
index d72c1899dc50..a4f0d1bf5848 100644
--- a/drivers/auxdisplay/line-display.h
+++ b/drivers/auxdisplay/line-display.h
@@ -14,12 +14,22 @@
#include <linux/device.h>
#include <linux/timer_types.h>

+struct linedisp;
+
+/**
+ * struct linedisp_ops - character line display operations
+ * @update: Function called to update the display. This must not sleep!
+ */
+struct linedisp_ops {
+ void (*update)(struct linedisp *linedisp);
+};
+
/**
* struct linedisp - character line display private data structure
* @dev: the line display device
* @id: instance id of this display
* @timer: timer used to implement scrolling
- * @update: function called to update the display
+ * @ops: character line display operations
* @buf: pointer to the buffer for the string currently displayed
* @message: the full message to display or scroll on the display
* @num_chars: the number of characters that can be displayed
@@ -31,7 +41,7 @@ struct linedisp {
struct device dev;
unsigned int id;
struct timer_list timer;
- void (*update)(struct linedisp *linedisp);
+ const struct linedisp_ops *ops;
char *buf;
char *message;
unsigned int num_chars;
@@ -41,8 +51,7 @@ struct linedisp {
};

int linedisp_register(struct linedisp *linedisp, struct device *parent,
- unsigned int num_chars, char *buf,
- void (*update)(struct linedisp *linedisp));
+ unsigned int num_chars, char *buf, const struct linedisp_ops *ops);
void linedisp_unregister(struct linedisp *linedisp);

#endif /* LINEDISP_H */
--
2.43.0.rc1.1.gbec44491f096