diff options
| author | Biju Das <biju.das.jz@bp.renesas.com> | 2023-02-27 11:41:51 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-09 17:21:54 +0100 |
| commit | 59d6558fb5fd750777edfde028ea1f9e7eed8a46 (patch) | |
| tree | ebcecca4eff12ba2a85d5c4caaf01a5542beda8b /drivers | |
| parent | 7eada8a122a2683ec63ad43982a4552b054d59ca (diff) | |
serial: 8250_em: Use pseudo offset for UART_FCR
UART_FCR shares the same offset with UART_IIR. We cannot use UART_FCR
in serial8250_em_serial_in() as it overlaps with UART_IIR.
Define UART_FCR_EM macro with a high value to avoid overlapping
with existing UART_* register defines and define another macro
UART_FCR_EM_HW for the real offset.
Use these macros in serial8250_em_serial{_in/_out} function to
read/write FCR register.
Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20230227114152.22265-7-biju.das.jz@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/tty/serial/8250/8250_em.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/drivers/tty/serial/8250/8250_em.c b/drivers/tty/serial/8250/8250_em.c index dcf1761e8ef5..7614ced9377e 100644 --- a/drivers/tty/serial/8250/8250_em.c +++ b/drivers/tty/serial/8250/8250_em.c @@ -19,6 +19,13 @@ #define UART_DLL_EM 9 #define UART_DLM_EM 10 +/* + * A high value for UART_FCR_EM avoids overlapping with existing UART_* + * register defines. UART_FCR_EM_HW is the real HW register offset. + */ +#define UART_FCR_EM 0x10003 +#define UART_FCR_EM_HW 3 + struct serial8250_em_priv { int line; }; @@ -29,12 +36,15 @@ static void serial8250_em_serial_out(struct uart_port *p, int offset, int value) case UART_TX: /* TX @ 0x00 */ writeb(value, p->membase); break; - case UART_FCR: /* FCR @ 0x0c (+1) */ case UART_LCR: /* LCR @ 0x10 (+1) */ case UART_MCR: /* MCR @ 0x14 (+1) */ case UART_SCR: /* SCR @ 0x20 (+1) */ writel(value, p->membase + ((offset + 1) << 2)); break; + case UART_FCR: + case UART_FCR_EM: + writel(value, p->membase + (UART_FCR_EM_HW << 2)); + break; case UART_IER: /* IER @ 0x04 */ value &= 0x0f; /* only 4 valid bits - not Xscale */ fallthrough; @@ -55,6 +65,8 @@ static unsigned int serial8250_em_serial_in(struct uart_port *p, int offset) case UART_MSR: /* MSR @ 0x1c (+1) */ case UART_SCR: /* SCR @ 0x20 (+1) */ return readl(p->membase + ((offset + 1) << 2)); + case UART_FCR_EM: + return readl(p->membase + (UART_FCR_EM_HW << 2)); case UART_IER: /* IER @ 0x04 */ case UART_IIR: /* IIR @ 0x08 */ case UART_DLL_EM: /* DLL @ 0x24 (+9) */ |