[PATCH 08/33] serial: 8250: sanitize uart_port::serial_{in,out}() types

Jiri Slaby (SUSE)
2025-06-11T10:03:43Z

uart_port::{serial_in,serial_out} (and plat_serial8250_port::* likewise)
historically use:
* 'unsigned int' for 32-bit register values in reads and writes, and
* 'int' for offsets.

Make them sane such that:
* 'u32' is used for register values, and
* 'unsigned int' is used for offsets.

While at it, name hooks' parameters, so it is clear what is what.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: "Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Vladimir Zapolskiy <vz@mleia.com>
Cc: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
---
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mips@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
---
arch/powerpc/kernel/legacy_serial.c | 7 ++---
drivers/tty/serial/8250/8250_dw.c | 34 ++++++++++++-------------
drivers/tty/serial/8250/8250_em.c | 4 +--
drivers/tty/serial/8250/8250_ingenic.c | 8 +++---
drivers/tty/serial/8250/8250_ioc3.c | 4 +--
drivers/tty/serial/8250/8250_lpc18xx.c | 2 +-
drivers/tty/serial/8250/8250_pci.c | 6 ++---
drivers/tty/serial/8250/8250_port.c | 30 +++++++++++-----------
drivers/tty/serial/8250/8250_rt288x.c | 4 +--
drivers/tty/serial/8250/8250_uniphier.c | 4 +--
include/linux/serial_8250.h | 4 +--
include/linux/serial_core.h | 4 +--
12 files changed, 56 insertions(+), 55 deletions(-)

diff --git a/arch/powerpc/kernel/legacy_serial.c b/arch/powerpc/kernel/legacy_serial.c
index a874eb8e000b..ae1906bfe8a5 100644
--- a/arch/powerpc/kernel/legacy_serial.c
+++ b/arch/powerpc/kernel/legacy_serial.c
@@ -54,9 +54,10 @@ static int legacy_serial_console = -1;
static const upf_t legacy_port_flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
UPF_SHARE_IRQ | UPF_FIXED_PORT;

-static unsigned int tsi_serial_in(struct uart_port *p, int offset)
+static u32 tsi_serial_in(struct uart_port *p, unsigned int offset)
{
- unsigned int tmp;
+ u32 tmp;
+
offset = offset << p->regshift;
if (offset == UART_IIR) {
tmp = readl(p->membase + (UART_IIR & ~3));
@@ -65,7 +66,7 @@ static unsigned int tsi_serial_in(struct uart_port *p, int offset)
return readb(p->membase + offset);
}

-static void tsi_serial_out(struct uart_port *p, int offset, int value)
+static void tsi_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
if (!((offset == UART_IER) && (value & UART_IER_UUE)))
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 1902f29444a1..0a22f0cb8896 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -67,8 +67,8 @@ struct dw8250_data {
struct dw8250_port_data data;
const struct dw8250_platform_data *pdata;

- int msr_mask_on;
- int msr_mask_off;
+ u32 msr_mask_on;
+ u32 msr_mask_off;
struct clk *clk;
struct clk *pclk;
struct notifier_block clk_notifier;
@@ -94,7 +94,7 @@ static inline struct dw8250_data *work_to_dw8250_data(struct work_struct *work)
return container_of(work, struct dw8250_data, clk_work);
}

-static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
+static inline u32 dw8250_modify_msr(struct uart_port *p, unsigned int offset, u32 value)
{
struct dw8250_data *d = to_dw8250_data(p->private_data);

@@ -145,7 +145,7 @@ static void dw8250_force_idle(struct uart_port *p)
* routine. Hence, it must not call serial_port_out() or serial_out()
* against the modified registers here, i.e. LCR.
*/
-static void dw8250_check_lcr(struct uart_port *p, int offset, int value)
+static void dw8250_check_lcr(struct uart_port *p, unsigned int offset, u32 value)
{
struct dw8250_data *d = to_dw8250_data(p->private_data);
void __iomem *addr = p->membase + (offset << p->regshift);
@@ -156,7 +156,7 @@ static void dw8250_check_lcr(struct uart_port *p, int offset, int value)

/* Make sure LCR write wasn't ignored */
while (tries--) {
- unsigned int lcr = serial_port_in(p, offset);
+ u32 lcr = serial_port_in(p, offset);

if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR))
return;
@@ -205,13 +205,13 @@ static void dw8250_tx_wait_empty(struct uart_port *p)
}
}

-static void dw8250_serial_out(struct uart_port *p, int offset, int value)
+static void dw8250_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
writeb(value, p->membase + (offset << p->regshift));
dw8250_check_lcr(p, offset, value);
}

-static void dw8250_serial_out38x(struct uart_port *p, int offset, int value)
+static void dw8250_serial_out38x(struct uart_port *p, unsigned int offset, u32 value)
{
/* Allow the TX to drain before we reconfigure */
if (offset == UART_LCR)
@@ -220,22 +220,22 @@ static void dw8250_serial_out38x(struct uart_port *p, int offset, int value)
dw8250_serial_out(p, offset, value);
}

-static unsigned int dw8250_serial_in(struct uart_port *p, int offset)
+static u32 dw8250_serial_in(struct uart_port *p, unsigned int offset)
{
- unsigned int value = readb(p->membase + (offset << p->regshift));
+ u32 value = readb(p->membase + (offset << p->regshift));

return dw8250_modify_msr(p, offset, value);
}

#ifdef CONFIG_64BIT
-static unsigned int dw8250_serial_inq(struct uart_port *p, int offset)
+static u32 dw8250_serial_inq(struct uart_port *p, unsigned int offset)
{
u8 value = __raw_readq(p->membase + (offset << p->regshift));

return dw8250_modify_msr(p, offset, value);
}

-static void dw8250_serial_outq(struct uart_port *p, int offset, int value)
+static void dw8250_serial_outq(struct uart_port *p, unsigned int offset, u32 value)
{
value &= 0xff;
__raw_writeq(value, p->membase + (offset << p->regshift));
@@ -246,28 +246,28 @@ static void dw8250_serial_outq(struct uart_port *p, int offset, int value)
}
#endif /* CONFIG_64BIT */

-static void dw8250_serial_out32(struct uart_port *p, int offset, int value)
+static void dw8250_serial_out32(struct uart_port *p, unsigned int offset, u32 value)
{
writel(value, p->membase + (offset << p->regshift));
dw8250_check_lcr(p, offset, value);
}

-static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
+static u32 dw8250_serial_in32(struct uart_port *p, unsigned int offset)
{
- unsigned int value = readl(p->membase + (offset << p->regshift));
+ u32 value = readl(p->membase + (offset << p->regshift));

return dw8250_modify_msr(p, offset, value);
}

-static void dw8250_serial_out32be(struct uart_port *p, int offset, int value)
+static void dw8250_serial_out32be(struct uart_port *p, unsigned int offset, u32 value)
{
iowrite32be(value, p->membase + (offset << p->regshift));
dw8250_check_lcr(p, offset, value);
}

-static unsigned int dw8250_serial_in32be(struct uart_port *p, int offset)
+static u32 dw8250_serial_in32be(struct uart_port *p, unsigned int offset)
{
- unsigned int value = ioread32be(p->membase + (offset << p->regshift));
+ u32 value = ioread32be(p->membase + (offset << p->regshift));

return dw8250_modify_msr(p, offset, value);
}
diff --git a/drivers/tty/serial/8250/8250_em.c b/drivers/tty/serial/8250/8250_em.c
index 35094f884492..e90c71494944 100644
--- a/drivers/tty/serial/8250/8250_em.c
+++ b/drivers/tty/serial/8250/8250_em.c
@@ -59,7 +59,7 @@ static void serial8250_em_serial_out_helper(struct uart_port *p, int offset,
}
}

-static unsigned int serial8250_em_serial_in(struct uart_port *p, int offset)
+static u32 serial8250_em_serial_in(struct uart_port *p, unsigned int offset)
{
switch (offset) {
case UART_RX: /* RX @ 0x00 */
@@ -119,7 +119,7 @@ static void serial8250_em_reg_update(struct uart_port *p, int off, int value)
serial8250_em_serial_out_helper(p, UART_HCR0_EM, hcr0);
}

-static void serial8250_em_serial_out(struct uart_port *p, int offset, int value)
+static void serial8250_em_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
switch (offset) {
case UART_TX:
diff --git a/drivers/tty/serial/8250/8250_ingenic.c b/drivers/tty/serial/8250/8250_ingenic.c
index a73dd3773640..94542fc143c2 100644
--- a/drivers/tty/serial/8250/8250_ingenic.c
+++ b/drivers/tty/serial/8250/8250_ingenic.c
@@ -168,9 +168,9 @@ OF_EARLYCON_DECLARE(jz4780_uart, "ingenic,jz4780-uart",
OF_EARLYCON_DECLARE(x1000_uart, "ingenic,x1000-uart",
ingenic_early_console_setup);

-static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
+static void ingenic_uart_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
- int ier;
+ u32 ier;

switch (offset) {
case UART_FCR:
@@ -206,9 +206,9 @@ static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
writeb(value, p->membase + (offset << p->regshift));
}

-static unsigned int ingenic_uart_serial_in(struct uart_port *p, int offset)
+static u32 ingenic_uart_serial_in(struct uart_port *p, unsigned int offset)
{
- unsigned int value;
+ u8 value;

value = readb(p->membase + (offset << p->regshift));

diff --git a/drivers/tty/serial/8250/8250_ioc3.c b/drivers/tty/serial/8250/8250_ioc3.c
index 499e80aa4cf9..3ebda9a5d07d 100644
--- a/drivers/tty/serial/8250/8250_ioc3.c
+++ b/drivers/tty/serial/8250/8250_ioc3.c
@@ -21,12 +21,12 @@ struct ioc3_8250_data {
int line;
};

-static unsigned int ioc3_serial_in(struct uart_port *p, int offset)
+static u32 ioc3_serial_in(struct uart_port *p, unsigned int offset)
{
return readb(p->membase + (offset ^ 3));
}

-static void ioc3_serial_out(struct uart_port *p, int offset, int value)
+static void ioc3_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
writeb(value, p->membase + (offset ^ 3));
}
diff --git a/drivers/tty/serial/8250/8250_lpc18xx.c b/drivers/tty/serial/8250/8250_lpc18xx.c
index d52445948da0..6c0489c9c253 100644
--- a/drivers/tty/serial/8250/8250_lpc18xx.c
+++ b/drivers/tty/serial/8250/8250_lpc18xx.c
@@ -67,7 +67,7 @@ static int lpc18xx_rs485_config(struct uart_port *port, struct ktermios *termios
return 0;
}

-static void lpc18xx_uart_serial_out(struct uart_port *p, int offset, int value)
+static void lpc18xx_uart_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
/*
* For DMA mode one must ensure that the UART_FCR_DMA_SELECT
diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index 73c200127b08..152f914c599d 100644
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -1751,7 +1751,7 @@ static int pci_fintek_init(struct pci_dev *dev)
return max_port;
}

-static void f815xxa_mem_serial_out(struct uart_port *p, int offset, int value)
+static void f815xxa_mem_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
struct f815xxa_data *data = p->private_data;
unsigned long flags;
@@ -1846,10 +1846,10 @@ static void kt_handle_break(struct uart_port *p)
serial8250_clear_and_reinit_fifos(up);
}

-static unsigned int kt_serial_in(struct uart_port *p, int offset)
+static u32 kt_serial_in(struct uart_port *p, unsigned int offset)
{
struct uart_8250_port *up = up_to_u8250p(p);
- unsigned int val;
+ u32 val;

/*
* When the Intel ME (management engine) gets reset its serial
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 6d7b8c4667c9..f5407832e8a7 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -339,14 +339,14 @@ static void default_serial_dl_write(struct uart_8250_port *up, u32 value)
}

#ifdef CONFIG_HAS_IOPORT
-static unsigned int hub6_serial_in(struct uart_port *p, int offset)
+static u32 hub6_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
outb(p->hub6 - 1 + offset, p->iobase);
return inb(p->iobase + 1);
}

-static void hub6_serial_out(struct uart_port *p, int offset, int value)
+static void hub6_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
outb(p->hub6 - 1 + offset, p->iobase);
@@ -354,73 +354,73 @@ static void hub6_serial_out(struct uart_port *p, int offset, int value)
}
#endif /* CONFIG_HAS_IOPORT */

-static unsigned int mem_serial_in(struct uart_port *p, int offset)
+static u32 mem_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
return readb(p->membase + offset);
}

-static void mem_serial_out(struct uart_port *p, int offset, int value)
+static void mem_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
writeb(value, p->membase + offset);
}

-static void mem16_serial_out(struct uart_port *p, int offset, int value)
+static void mem16_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
writew(value, p->membase + offset);
}

-static unsigned int mem16_serial_in(struct uart_port *p, int offset)
+static u32 mem16_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
return readw(p->membase + offset);
}

-static void mem32_serial_out(struct uart_port *p, int offset, int value)
+static void mem32_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
writel(value, p->membase + offset);
}

-static unsigned int mem32_serial_in(struct uart_port *p, int offset)
+static u32 mem32_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
return readl(p->membase + offset);
}

-static void mem32be_serial_out(struct uart_port *p, int offset, int value)
+static void mem32be_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
iowrite32be(value, p->membase + offset);
}

-static unsigned int mem32be_serial_in(struct uart_port *p, int offset)
+static u32 mem32be_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
return ioread32be(p->membase + offset);
}

#ifdef CONFIG_HAS_IOPORT
-static unsigned int io_serial_in(struct uart_port *p, int offset)
+static u32 io_serial_in(struct uart_port *p, unsigned int offset)
{
offset = offset << p->regshift;
return inb(p->iobase + offset);
}

-static void io_serial_out(struct uart_port *p, int offset, int value)
+static void io_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
offset = offset << p->regshift;
outb(value, p->iobase + offset);
}
#endif
-static unsigned int no_serial_in(struct uart_port *p, int offset)
+static u32 no_serial_in(struct uart_port *p, unsigned int offset)
{
- return (unsigned int)-1;
+ return ~0U;
}

-static void no_serial_out(struct uart_port *p, int offset, int value)
+static void no_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
}

diff --git a/drivers/tty/serial/8250/8250_rt288x.c b/drivers/tty/serial/8250/8250_rt288x.c
index 6415ca8d3adf..bf28b8a9a710 100644
--- a/drivers/tty/serial/8250/8250_rt288x.c
+++ b/drivers/tty/serial/8250/8250_rt288x.c
@@ -33,7 +33,7 @@ static const u8 au_io_out_map[5] = {
[UART_MCR] = 6,
};

-static unsigned int au_serial_in(struct uart_port *p, int offset)
+static u32 au_serial_in(struct uart_port *p, unsigned int offset)
{
if (offset >= ARRAY_SIZE(au_io_in_map))
return UINT_MAX;
@@ -42,7 +42,7 @@ static unsigned int au_serial_in(struct uart_port *p, int offset)
return __raw_readl(p->membase + (offset << p->regshift));
}

-static void au_serial_out(struct uart_port *p, int offset, int value)
+static void au_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
if (offset >= ARRAY_SIZE(au_io_out_map))
return;
diff --git a/drivers/tty/serial/8250/8250_uniphier.c b/drivers/tty/serial/8250/8250_uniphier.c
index 4874a9632db3..e3db60bf50c9 100644
--- a/drivers/tty/serial/8250/8250_uniphier.c
+++ b/drivers/tty/serial/8250/8250_uniphier.c
@@ -63,7 +63,7 @@ OF_EARLYCON_DECLARE(uniphier, "socionext,uniphier-uart",
* The register map is slightly different from that of 8250.
* IO callbacks must be overridden for correct access to FCR, LCR, MCR and SCR.
*/
-static unsigned int uniphier_serial_in(struct uart_port *p, int offset)
+static u32 uniphier_serial_in(struct uart_port *p, unsigned int offset)
{
unsigned int valshift = 0;

@@ -92,7 +92,7 @@ static unsigned int uniphier_serial_in(struct uart_port *p, int offset)
return (readl(p->membase + offset) >> valshift) & 0xff;
}

-static void uniphier_serial_out(struct uart_port *p, int offset, int value)
+static void uniphier_serial_out(struct uart_port *p, unsigned int offset, u32 value)
{
unsigned int valshift = 0;
bool normal = false;
diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 144de7a7948d..01efdce0fda0 100644
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -46,8 +46,8 @@ struct plat_serial8250_port {
unsigned int type; /* If UPF_FIXED_TYPE */
upf_t flags; /* UPF_* flags */
u16 bugs; /* port bugs */
- unsigned int (*serial_in)(struct uart_port *, int);
- void (*serial_out)(struct uart_port *, int, int);
+ u32 (*serial_in)(struct uart_port *, unsigned int offset);
+ void (*serial_out)(struct uart_port *, unsigned int offset, u32 val);
u32 (*dl_read)(struct uart_8250_port *up);
void (*dl_write)(struct uart_8250_port *up, u32 value);
void (*set_termios)(struct uart_port *,
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 914b5e97e056..d65b15449cfe 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -443,8 +443,8 @@ struct uart_port {
spinlock_t lock; /* port lock */
unsigned long iobase; /* in/out[bwl] */
unsigned char __iomem *membase; /* read/write[bwl] */
- unsigned int (*serial_in)(struct uart_port *, int);
- void (*serial_out)(struct uart_port *, int, int);
+ u32 (*serial_in)(struct uart_port *, unsigned int offset);
+ void (*serial_out)(struct uart_port *, unsigned int offset, u32 val);
void (*set_termios)(struct uart_port *,
struct ktermios *new,
const struct ktermios *old);
--
2.49.0