From 403753937020549e4bb0d8ef6e915f00a338a096 Mon Sep 17 00:00:00 2001 From: Peter Hurley Date: Tue, 24 Feb 2015 14:25:14 -0500 Subject: [PATCH] serial: 8250: Decouple RSA probe Prepare for 8250 split; separate RSA probe and resource management from base port operations. Override base port operations for the config_port(), request_port() and release_port() methods to implement the optional RSA probe and resource management only in the universal/legacy 8250 driver. Introduce 'probe' flags for 8250 ports, which allows drivers higher up the driver stack to enable optional probes. Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250.h | 3 - drivers/tty/serial/8250/8250_core.c | 112 +++++++++++++++++++--------- include/linux/serial_8250.h | 2 + 3 files changed, 78 insertions(+), 39 deletions(-) diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h index 23dc9f9b9839..c43f74c53cd9 100644 --- a/drivers/tty/serial/8250/8250.h +++ b/drivers/tty/serial/8250/8250.h @@ -84,9 +84,6 @@ struct serial8250_config { #define UART_BUG_THRE (1 << 3) /* UART has buggy THRE reassertion */ #define UART_BUG_PARITY (1 << 4) /* UART mishandles parity if FIFO enabled */ -#define PROBE_RSA (1 << 0) -#define PROBE_ANY (~0) - #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8) #ifdef CONFIG_SERIAL_8250_SHARE_IRQ diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 257e373bfccd..a4ed84a4f8db 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -1105,7 +1105,7 @@ static void autoconfig_16550a(struct uart_8250_port *up) * whether or not this UART is a 16550A or not, since this will * determine whether or not we can use its FIFO features or not. */ -static void autoconfig(struct uart_8250_port *up, unsigned int probeflags) +static void autoconfig(struct uart_8250_port *up) { unsigned char status1, scratch, scratch2, scratch3; unsigned char save_lcr, save_mcr; @@ -1228,7 +1228,7 @@ static void autoconfig(struct uart_8250_port *up, unsigned int probeflags) /* * Only probe for RSA ports if we got the region. */ - if (port->type == PORT_16550A && probeflags & PROBE_RSA && + if (port->type == PORT_16550A && up->probe & UART_PROBE_RSA && __enable_rsa(up)) port->type = PORT_RSA; #endif @@ -2832,10 +2832,6 @@ static void serial8250_release_port(struct uart_port *port) struct uart_8250_port *up = up_to_u8250p(port); serial8250_release_std_resource(up); -#ifdef CONFIG_SERIAL_8250_RSA - if (port->type == PORT_RSA) - serial8250_release_rsa_resource(up); -#endif } static int serial8250_request_port(struct uart_port *port) @@ -2847,13 +2843,6 @@ static int serial8250_request_port(struct uart_port *port) return -ENODEV; ret = serial8250_request_std_resource(up); -#ifdef CONFIG_SERIAL_8250_RSA - if (ret == 0 && port->type == PORT_RSA) { - ret = serial8250_request_rsa_resource(up); - if (ret < 0) - serial8250_release_std_resource(up); - } -#endif return ret; } @@ -3001,7 +2990,6 @@ static void register_dev_spec_attr_grp(struct uart_8250_port *up) static void serial8250_config_port(struct uart_port *port, int flags) { struct uart_8250_port *up = up_to_u8250p(port); - int probeflags = 0; int ret; if (port->type == PORT_8250_CIR) @@ -3015,28 +3003,11 @@ static void serial8250_config_port(struct uart_port *port, int flags) if (ret < 0) return; -#ifdef CONFIG_SERIAL_8250_RSA - if (port->type == PORT_RSA) { - if (serial8250_request_rsa_resource(up) == 0) - probeflags |= PROBE_RSA; - } else if (flags & UART_CONFIG_TYPE) { - int i; - - for (i = 0 ; i < probe_rsa_count; ++i) { - if (probe_rsa[i] == port->iobase) { - if (serial8250_request_rsa_resource(up) == 0) - probeflags |= PROBE_RSA; - break; - } - } - } -#endif - if (port->iotype != up->cur_iotype) set_io_from_upio(port); if (flags & UART_CONFIG_TYPE) - autoconfig(up, probeflags); + autoconfig(up); /* if access method is AU, it is a 16550 with a quirk */ if (port->type == PORT_16550A && port->iotype == UPIO_AU) @@ -3049,10 +3020,6 @@ static void serial8250_config_port(struct uart_port *port, int flags) if (port->type != PORT_UNKNOWN && flags & UART_CONFIG_IRQ) autoconfig_irq(up); -#ifdef CONFIG_SERIAL_8250_RSA - if (port->type != PORT_RSA && probeflags & PROBE_RSA) - serial8250_release_rsa_resource(up); -#endif if (port->type == PORT_UNKNOWN) serial8250_release_std_resource(up); @@ -3113,6 +3080,9 @@ static struct uart_ops serial8250_pops = { #endif }; +static const struct uart_ops *base_ops; +static struct uart_ops univ8250_port_ops; + static const struct uart_8250_ops univ8250_driver_ops = { .setup_irq = univ8250_setup_irq, .release_irq = univ8250_release_irq, @@ -3184,6 +3154,69 @@ static void serial8250_set_defaults(struct uart_8250_port *up) } } +#ifdef CONFIG_SERIAL_8250_RSA + +static void univ8250_config_port(struct uart_port *port, int flags) +{ + struct uart_8250_port *up = up_to_u8250p(port); + + up->probe &= ~UART_PROBE_RSA; + if (port->type == PORT_RSA) { + if (serial8250_request_rsa_resource(up) == 0) + up->probe |= UART_PROBE_RSA; + } else if (flags & UART_CONFIG_TYPE) { + int i; + + for (i = 0; i < probe_rsa_count; i++) { + if (probe_rsa[i] == up->port.iobase) { + if (serial8250_request_rsa_resource(up) == 0) + up->probe |= UART_PROBE_RSA; + break; + } + } + } + + base_ops->config_port(port, flags); + + if (port->type != PORT_RSA && up->probe & UART_PROBE_RSA) + serial8250_release_rsa_resource(up); +} + +static int univ8250_request_port(struct uart_port *port) +{ + struct uart_8250_port *up = up_to_u8250p(port); + int ret; + + ret = base_ops->request_port(port); + if (ret == 0 && port->type == PORT_RSA) { + ret = serial8250_request_rsa_resource(up); + if (ret < 0) + base_ops->release_port(port); + } + + return ret; +} + +static void univ8250_release_port(struct uart_port *port) +{ + struct uart_8250_port *up = up_to_u8250p(port); + + if (port->type == PORT_RSA) + serial8250_release_rsa_resource(up); + base_ops->release_port(port); +} + +static void univ8250_rsa_support(struct uart_ops *ops) +{ + ops->config_port = univ8250_config_port; + ops->request_port = univ8250_request_port; + ops->release_port = univ8250_release_port; +} + +#else +#define univ8250_rsa_support(x) do { } while (0) +#endif /* CONFIG_SERIAL_8250_RSA */ + static void __init serial8250_isa_init_ports(void) { struct uart_8250_port *up; @@ -3203,6 +3236,9 @@ static void __init serial8250_isa_init_ports(void) port->line = i; serial8250_init_port(up); + if (!base_ops) + base_ops = port->ops; + port->ops = &univ8250_port_ops; init_timer(&up->timer); up->timer.function = serial8250_timeout; @@ -3216,6 +3252,10 @@ static void __init serial8250_isa_init_ports(void) up->mcr_force = ALPHA_KLUDGE_MCR; } + /* chain base port ops to support Remote Supervisor Adapter */ + univ8250_port_ops = *base_ops; + univ8250_rsa_support(&univ8250_port_ops); + if (share_irqs) irqflag = IRQF_SHARED; diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h index 50735a9ad598..78097e7a330a 100644 --- a/include/linux/serial_8250.h +++ b/include/linux/serial_8250.h @@ -102,6 +102,8 @@ struct uart_8250_port { unsigned char canary; /* non-zero during system sleep * if no_console_suspend */ + unsigned char probe; +#define UART_PROBE_RSA (1 << 0) /* * Some bits in registers are cleared on a read, so they must