tty: goldfish: Refactor constants to better reflect their nature
authorAleksandar Markovic <aleksandar.markovic@imgtec.com>
Tue, 29 Aug 2017 13:53:18 +0000 (15:53 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 31 Aug 2017 16:58:45 +0000 (18:58 +0200)
Classify constants GOLDFISH_TTY_xxx into two groups: command ids and
register offsets. Apply different naming for register offsets (add
'REG_' after 'GOLDFISH_TTY_' in constant names). Change implementation
to use preprocessor's '#define' statements instead of 'enum'
declaration (as this is more common way of implementation in such
cases).

This makes the driver code easier to follow and hopefully prevents
future bugs.

Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/goldfish.c

index 996bd47..011eb53 100644 (file)
 #include <linux/module.h>
 #include <linux/goldfish.h>
 
-enum {
-       GOLDFISH_TTY_PUT_CHAR       = 0x00,
-       GOLDFISH_TTY_BYTES_READY    = 0x04,
-       GOLDFISH_TTY_CMD            = 0x08,
-
-       GOLDFISH_TTY_DATA_PTR       = 0x10,
-       GOLDFISH_TTY_DATA_LEN       = 0x14,
-       GOLDFISH_TTY_DATA_PTR_HIGH  = 0x18,
-
-       GOLDFISH_TTY_CMD_INT_DISABLE    = 0,
-       GOLDFISH_TTY_CMD_INT_ENABLE     = 1,
-       GOLDFISH_TTY_CMD_WRITE_BUFFER   = 2,
-       GOLDFISH_TTY_CMD_READ_BUFFER    = 3,
-};
+/* Goldfish tty register's offsets */
+#define        GOLDFISH_TTY_REG_BYTES_READY    0x04
+#define        GOLDFISH_TTY_REG_CMD            0x08
+#define        GOLDFISH_TTY_REG_DATA_PTR       0x10
+#define        GOLDFISH_TTY_REG_DATA_LEN       0x14
+#define        GOLDFISH_TTY_REG_DATA_PTR_HIGH  0x18
+
+/* Goldfish tty commands */
+#define        GOLDFISH_TTY_CMD_INT_DISABLE    0
+#define        GOLDFISH_TTY_CMD_INT_ENABLE     1
+#define        GOLDFISH_TTY_CMD_WRITE_BUFFER   2
+#define        GOLDFISH_TTY_CMD_READ_BUFFER    3
 
 struct goldfish_tty {
        struct tty_port port;
@@ -59,10 +57,10 @@ static void goldfish_tty_do_write(int line, const char *buf, unsigned count)
        struct goldfish_tty *qtty = &goldfish_ttys[line];
        void __iomem *base = qtty->base;
        spin_lock_irqsave(&qtty->lock, irq_flags);
-       gf_write_ptr(buf, base + GOLDFISH_TTY_DATA_PTR,
-                               base + GOLDFISH_TTY_DATA_PTR_HIGH);
-       writel(count, base + GOLDFISH_TTY_DATA_LEN);
-       writel(GOLDFISH_TTY_CMD_WRITE_BUFFER, base + GOLDFISH_TTY_CMD);
+       gf_write_ptr(buf, base + GOLDFISH_TTY_REG_DATA_PTR,
+                    base + GOLDFISH_TTY_REG_DATA_PTR_HIGH);
+       writel(count, base + GOLDFISH_TTY_REG_DATA_LEN);
+       writel(GOLDFISH_TTY_CMD_WRITE_BUFFER, base + GOLDFISH_TTY_REG_CMD);
        spin_unlock_irqrestore(&qtty->lock, irq_flags);
 }
 
@@ -74,16 +72,16 @@ static irqreturn_t goldfish_tty_interrupt(int irq, void *dev_id)
        unsigned char *buf;
        u32 count;
 
-       count = readl(base + GOLDFISH_TTY_BYTES_READY);
+       count = readl(base + GOLDFISH_TTY_REG_BYTES_READY);
        if (count == 0)
                return IRQ_NONE;
 
        count = tty_prepare_flip_string(&qtty->port, &buf, count);
        spin_lock_irqsave(&qtty->lock, irq_flags);
-       gf_write_ptr(buf, base + GOLDFISH_TTY_DATA_PTR,
-                               base + GOLDFISH_TTY_DATA_PTR_HIGH);
-       writel(count, base + GOLDFISH_TTY_DATA_LEN);
-       writel(GOLDFISH_TTY_CMD_READ_BUFFER, base + GOLDFISH_TTY_CMD);
+       gf_write_ptr(buf, base + GOLDFISH_TTY_REG_DATA_PTR,
+                    base + GOLDFISH_TTY_REG_DATA_PTR_HIGH);
+       writel(count, base + GOLDFISH_TTY_REG_DATA_LEN);
+       writel(GOLDFISH_TTY_CMD_READ_BUFFER, base + GOLDFISH_TTY_REG_CMD);
        spin_unlock_irqrestore(&qtty->lock, irq_flags);
        tty_schedule_flip(&qtty->port);
        return IRQ_HANDLED;
@@ -93,7 +91,7 @@ static int goldfish_tty_activate(struct tty_port *port, struct tty_struct *tty)
 {
        struct goldfish_tty *qtty = container_of(port, struct goldfish_tty,
                                                                        port);
-       writel(GOLDFISH_TTY_CMD_INT_ENABLE, qtty->base + GOLDFISH_TTY_CMD);
+       writel(GOLDFISH_TTY_CMD_INT_ENABLE, qtty->base + GOLDFISH_TTY_REG_CMD);
        return 0;
 }
 
@@ -101,7 +99,7 @@ static void goldfish_tty_shutdown(struct tty_port *port)
 {
        struct goldfish_tty *qtty = container_of(port, struct goldfish_tty,
                                                                        port);
-       writel(GOLDFISH_TTY_CMD_INT_DISABLE, qtty->base + GOLDFISH_TTY_CMD);
+       writel(GOLDFISH_TTY_CMD_INT_DISABLE, qtty->base + GOLDFISH_TTY_REG_CMD);
 }
 
 static int goldfish_tty_open(struct tty_struct *tty, struct file *filp)
@@ -136,7 +134,7 @@ static int goldfish_tty_chars_in_buffer(struct tty_struct *tty)
 {
        struct goldfish_tty *qtty = &goldfish_ttys[tty->index];
        void __iomem *base = qtty->base;
-       return readl(base + GOLDFISH_TTY_BYTES_READY);
+       return readl(base + GOLDFISH_TTY_REG_BYTES_READY);
 }
 
 static void goldfish_tty_console_write(struct console *co, const char *b,
@@ -272,7 +270,7 @@ static int goldfish_tty_probe(struct platform_device *pdev)
        qtty->base = base;
        qtty->irq = irq;
 
-       writel(GOLDFISH_TTY_CMD_INT_DISABLE, base + GOLDFISH_TTY_CMD);
+       writel(GOLDFISH_TTY_CMD_INT_DISABLE, base + GOLDFISH_TTY_REG_CMD);
 
        ret = request_irq(irq, goldfish_tty_interrupt, IRQF_SHARED,
                                                "goldfish_tty", qtty);