1 // SPDX-License-Identifier: GPL-2.0+
2
3 #include <linux/errno.h>
4 #include <linux/ioport.h>
5 #include <linux/module.h>
6 #include <linux/moduleparam.h>
7
8 #include <linux/serial.h>
9 #include <linux/serial_8250.h>
10
11 #include "8250.h"
12
13 #define PORT_RSA_MAX 4
14 static unsigned long probe_rsa[PORT_RSA_MAX];
15 static unsigned int probe_rsa_count;
16
rsa8250_request_resource(struct uart_8250_port * up)17 static int rsa8250_request_resource(struct uart_8250_port *up)
18 {
19 unsigned long start = UART_RSA_BASE << up->port.regshift;
20 unsigned int size = 8 << up->port.regshift;
21 struct uart_port *port = &up->port;
22 int ret = -EINVAL;
23
24 switch (port->iotype) {
25 case UPIO_HUB6:
26 case UPIO_PORT:
27 start += port->iobase;
28 if (request_region(start, size, "serial-rsa"))
29 ret = 0;
30 else
31 ret = -EBUSY;
32 break;
33 }
34
35 return ret;
36 }
37
rsa8250_release_resource(struct uart_8250_port * up)38 static void rsa8250_release_resource(struct uart_8250_port *up)
39 {
40 unsigned long offset = UART_RSA_BASE << up->port.regshift;
41 unsigned int size = 8 << up->port.regshift;
42 struct uart_port *port = &up->port;
43
44 switch (port->iotype) {
45 case UPIO_HUB6:
46 case UPIO_PORT:
47 release_region(port->iobase + offset, size);
48 break;
49 }
50 }
51
univ8250_config_port(struct uart_port * port,int flags)52 static void univ8250_config_port(struct uart_port *port, int flags)
53 {
54 struct uart_8250_port *up = up_to_u8250p(port);
55 unsigned int i;
56
57 up->probe &= ~UART_PROBE_RSA;
58 if (port->type == PORT_RSA) {
59 if (rsa8250_request_resource(up) == 0)
60 up->probe |= UART_PROBE_RSA;
61 } else if (flags & UART_CONFIG_TYPE) {
62 for (i = 0; i < probe_rsa_count; i++) {
63 if (probe_rsa[i] == up->port.iobase) {
64 if (rsa8250_request_resource(up) == 0)
65 up->probe |= UART_PROBE_RSA;
66 break;
67 }
68 }
69 }
70
71 univ8250_port_base_ops->config_port(port, flags);
72
73 if (port->type != PORT_RSA && up->probe & UART_PROBE_RSA)
74 rsa8250_release_resource(up);
75 }
76
univ8250_request_port(struct uart_port * port)77 static int univ8250_request_port(struct uart_port *port)
78 {
79 struct uart_8250_port *up = up_to_u8250p(port);
80 int ret;
81
82 ret = univ8250_port_base_ops->request_port(port);
83 if (ret == 0 && port->type == PORT_RSA) {
84 ret = rsa8250_request_resource(up);
85 if (ret < 0)
86 univ8250_port_base_ops->release_port(port);
87 }
88
89 return ret;
90 }
91
univ8250_release_port(struct uart_port * port)92 static void univ8250_release_port(struct uart_port *port)
93 {
94 struct uart_8250_port *up = up_to_u8250p(port);
95
96 if (port->type == PORT_RSA)
97 rsa8250_release_resource(up);
98 univ8250_port_base_ops->release_port(port);
99 }
100
univ8250_rsa_support(struct uart_ops * ops)101 void univ8250_rsa_support(struct uart_ops *ops)
102 {
103 ops->config_port = univ8250_config_port;
104 ops->request_port = univ8250_request_port;
105 ops->release_port = univ8250_release_port;
106 }
107
108 module_param_hw_array(probe_rsa, ulong, ioport, &probe_rsa_count, 0444);
109 MODULE_PARM_DESC(probe_rsa, "Probe I/O ports for RSA");
110
111 #ifdef CONFIG_SERIAL_8250_DEPRECATED_OPTIONS
112 #ifndef MODULE
113 /*
114 * Keep the old "8250" name working as well for the module options so we don't
115 * break people. We need to keep the names identical and the convenient macros
116 * will happily refuse to let us do that by failing the build with redefinition
117 * errors of global variables. So we stick them inside a dummy function to
118 * avoid those conflicts. The options still get parsed, and the redefined
119 * MODULE_PARAM_PREFIX lets us keep the "8250." syntax alive.
120 *
121 * This is hacky. I'm sorry.
122 */
rsa8250_options(void)123 static void __used rsa8250_options(void)
124 {
125 #undef MODULE_PARAM_PREFIX
126 #define MODULE_PARAM_PREFIX "8250_core."
127
128 __module_param_call(MODULE_PARAM_PREFIX, probe_rsa,
129 ¶m_array_ops, .arr = &__param_arr_probe_rsa,
130 0444, -1, 0);
131 }
132 #endif
133 #endif
134