| 1 | Add a new UART I/O type for slow busses such as the ixp4xx expansion bus |
| 2 | --- a/include/linux/serial_8250.h |
| 3 | +++ b/include/linux/serial_8250.h |
| 4 | @@ -27,6 +27,7 @@ struct plat_serial8250_port { |
| 5 | void *private_data; |
| 6 | unsigned char regshift; /* register shift */ |
| 7 | unsigned char iotype; /* UPIO_* */ |
| 8 | + unsigned int rw_delay; /* udelay for slower busses IXP4XX Expansion Bus */ |
| 9 | unsigned char hub6; |
| 10 | upf_t flags; /* UPF_* flags */ |
| 11 | unsigned int type; /* If UPF_FIXED_TYPE */ |
| 12 | --- a/include/linux/serial_core.h |
| 13 | +++ b/include/linux/serial_core.h |
| 14 | @@ -324,6 +324,7 @@ struct uart_port { |
| 15 | #define UPIO_AU (4) /* Au1x00 type IO */ |
| 16 | #define UPIO_TSI (5) /* Tsi108/109 type IO */ |
| 17 | #define UPIO_RM9000 (6) /* RM9000 type IO */ |
| 18 | +#define UPIO_MEM_DELAY (7) |
| 19 | |
| 20 | unsigned int read_status_mask; /* driver specific */ |
| 21 | unsigned int ignore_status_mask; /* driver specific */ |
| 22 | @@ -368,6 +369,7 @@ struct uart_port { |
| 23 | |
| 24 | unsigned int mctrl; /* current modem ctrl settings */ |
| 25 | unsigned int timeout; /* character-based timeout */ |
| 26 | + unsigned int rw_delay; /* udelay for slow busses, IXP4XX Expansion Bus */ |
| 27 | unsigned int type; /* port type */ |
| 28 | const struct uart_ops *ops; |
| 29 | unsigned int custom_divisor; |
| 30 | --- a/drivers/tty/serial/8250/8250.c |
| 31 | +++ b/drivers/tty/serial/8250/8250.c |
| 32 | @@ -400,6 +400,20 @@ static void mem_serial_out(struct uart_p |
| 33 | writeb(value, p->membase + offset); |
| 34 | } |
| 35 | |
| 36 | +static unsigned int memdelay_serial_in(struct uart_port *p, int offset) |
| 37 | +{ |
| 38 | + struct uart_8250_port *up = (struct uart_8250_port *)p; |
| 39 | + udelay(up->port.rw_delay); |
| 40 | + return mem_serial_in(p, offset); |
| 41 | +} |
| 42 | + |
| 43 | +static void memdelay_serial_out(struct uart_port *p, int offset, int value) |
| 44 | +{ |
| 45 | + struct uart_8250_port *up = (struct uart_8250_port *)p; |
| 46 | + udelay(up->port.rw_delay); |
| 47 | + mem_serial_out(p, offset, value); |
| 48 | +} |
| 49 | + |
| 50 | static void mem32_serial_out(struct uart_port *p, int offset, int value) |
| 51 | { |
| 52 | offset = map_8250_out_reg(p, offset) << p->regshift; |
| 53 | @@ -459,6 +473,11 @@ static void set_io_from_upio(struct uart |
| 54 | p->serial_out = mem32_serial_out; |
| 55 | break; |
| 56 | |
| 57 | + case UPIO_MEM_DELAY: |
| 58 | + p->serial_in = memdelay_serial_in; |
| 59 | + p->serial_out = memdelay_serial_out; |
| 60 | + break; |
| 61 | + |
| 62 | case UPIO_AU: |
| 63 | p->serial_in = au_serial_in; |
| 64 | p->serial_out = au_serial_out; |
| 65 | @@ -481,6 +500,7 @@ serial_out_sync(struct uart_8250_port *u |
| 66 | switch (p->iotype) { |
| 67 | case UPIO_MEM: |
| 68 | case UPIO_MEM32: |
| 69 | + case UPIO_MEM_DELAY: |
| 70 | case UPIO_AU: |
| 71 | p->serial_out(p, offset, value); |
| 72 | p->serial_in(p, UART_LCR); /* safe, no side-effects */ |
| 73 | @@ -2498,6 +2518,7 @@ static int serial8250_request_std_resour |
| 74 | case UPIO_TSI: |
| 75 | case UPIO_MEM32: |
| 76 | case UPIO_MEM: |
| 77 | + case UPIO_MEM_DELAY: |
| 78 | if (!up->port.mapbase) |
| 79 | break; |
| 80 | |
| 81 | @@ -2534,6 +2555,7 @@ static void serial8250_release_std_resou |
| 82 | case UPIO_TSI: |
| 83 | case UPIO_MEM32: |
| 84 | case UPIO_MEM: |
| 85 | + case UPIO_MEM_DELAY: |
| 86 | if (!up->port.mapbase) |
| 87 | break; |
| 88 | |
| 89 | @@ -3050,6 +3072,7 @@ static int __devinit serial8250_probe(st |
| 90 | port.set_termios = p->set_termios; |
| 91 | port.pm = p->pm; |
| 92 | port.dev = &dev->dev; |
| 93 | + port.rw_delay = p->rw_delay; |
| 94 | port.irqflags |= irqflag; |
| 95 | ret = serial8250_register_port(&port); |
| 96 | if (ret < 0) { |
| 97 | @@ -3199,6 +3222,7 @@ int serial8250_register_port(struct uart |
| 98 | uart->port.iotype = port->iotype; |
| 99 | uart->port.flags = port->flags | UPF_BOOT_AUTOCONF; |
| 100 | uart->port.mapbase = port->mapbase; |
| 101 | + uart->port.rw_delay = port->rw_delay; |
| 102 | uart->port.private_data = port->private_data; |
| 103 | if (port->dev) |
| 104 | uart->port.dev = port->dev; |
| 105 | --- a/drivers/tty/serial/serial_core.c |
| 106 | +++ b/drivers/tty/serial/serial_core.c |
| 107 | @@ -2021,6 +2021,7 @@ uart_report_port(struct uart_driver *drv |
| 108 | snprintf(address, sizeof(address), |
| 109 | "I/O 0x%lx offset 0x%x", port->iobase, port->hub6); |
| 110 | break; |
| 111 | + case UPIO_MEM_DELAY: |
| 112 | case UPIO_MEM: |
| 113 | case UPIO_MEM32: |
| 114 | case UPIO_AU: |
| 115 | @@ -2436,6 +2437,7 @@ int uart_match_port(struct uart_port *po |
| 116 | case UPIO_HUB6: |
| 117 | return (port1->iobase == port2->iobase) && |
| 118 | (port1->hub6 == port2->hub6); |
| 119 | + case UPIO_MEM_DELAY: |
| 120 | case UPIO_MEM: |
| 121 | case UPIO_MEM32: |
| 122 | case UPIO_AU: |
| 123 | |
