add dts config

hc

2023-12-06 08f87f769b595151be1afeff53e144f543faa614

 kernel/drivers/tty/serial/8250/8250_fsl.c
..
..
@@ -1,15 +1,12 @@
1
1
 // SPDX-License-Identifier: GPL-2.0
2
-#include <linux/serial_reg.h>
3
-#include <linux/serial_8250.h>
4
-
5
-#include "8250.h"
6
-
7
2
 /*
8
3
  * Freescale 16550 UART "driver", Copyright (C) 2011 Paul Gortmaker.
4
+ * Copyright 2020 NXP
5
+ * Copyright 2020 Puresoftware Ltd.
9
6
  *
10
7
  * This isn't a full driver; it just provides an alternate IRQ
11
- * handler to deal with an errata.  Everything else is just
12
- * using the bog standard 8250 support.
8
+ * handler to deal with an errata and provide ACPI wrapper.
9
+ * Everything else is just using the bog standard 8250 support.
13
10
  *
14
11
  * We follow code flow of serial8250_default_handle_irq() but add
15
12
  * a check for a break and insert a dummy read on the Rx for the
..
..
@@ -19,6 +16,16 @@
19
16
  * field to carry the "what we just did" information from the one
20
17
  * IRQ event to the next one.
21
18
  */
19
+
20
+#include <linux/acpi.h>
21
+#include <linux/serial_reg.h>
22
+#include <linux/serial_8250.h>
23
+
24
+#include "8250.h"
25
+
26
+struct fsl8250_data {
27
+	int	line;
28
+};
22
29
 
23
30
 int fsl8250_handle_irq(struct uart_port *port)
24
31
 {
..
..
@@ -53,9 +60,18 @@
53
60
 
54
61
 	/* Stop processing interrupts on input overrun */
55
62
 	if ((orig_lsr & UART_LSR_OE) && (up->overrun_backoff_time_ms > 0)) {
63
+		unsigned int ca_flags;
56
64
 		unsigned long delay;
65
+		bool is_console;
57
66
 
67
+		is_console = uart_console(port);
68
+
69
+		if (is_console)
70
+			console_atomic_lock(&ca_flags);
58
71
 		up->ier = port->serial_in(port, UART_IER);
72
+		if (is_console)
73
+			console_atomic_unlock(ca_flags);
74
+
59
75
 		if (up->ier & (UART_IER_RLSI | UART_IER_RDI)) {
60
76
 			port->ops->stop_rx(port);
61
77
 		} else {
..
..
@@ -71,11 +87,98 @@
71
87
 
72
88
 	serial8250_modem_status(up);
73
89
 
74
-	if (lsr & UART_LSR_THRE)
90
+	if ((lsr & UART_LSR_THRE) && (up->ier & UART_IER_THRI))
75
91
 		serial8250_tx_chars(up);
76
92
 
77
93
 	up->lsr_saved_flags = orig_lsr;
78
-	spin_unlock_irqrestore(&up->port.lock, flags);
94
+	uart_unlock_and_check_sysrq(&up->port, flags);
79
95
 	return 1;
80
96
 }
81
97
 EXPORT_SYMBOL_GPL(fsl8250_handle_irq);
98
+
99
+#ifdef CONFIG_ACPI
100
+static int fsl8250_acpi_probe(struct platform_device *pdev)
101
+{
102
+	struct fsl8250_data *data;
103
+	struct uart_8250_port port8250;
104
+	struct device *dev = &pdev->dev;
105
+	struct resource *regs;
106
+
107
+	int ret, irq;
108
+
109
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
110
+	if (!regs) {
111
+		dev_err(dev, "no registers defined\n");
112
+		return -EINVAL;
113
+	}
114
+
115
+	irq = platform_get_irq(pdev, 0);
116
+	if (irq < 0) {
117
+		if (irq != -EPROBE_DEFER)
118
+			dev_err(dev, "cannot get irq\n");
119
+		return irq;
120
+	}
121
+
122
+	memset(&port8250, 0, sizeof(port8250));
123
+
124
+	ret = device_property_read_u32(dev, "clock-frequency",
125
+					&port8250.port.uartclk);
126
+	if (ret)
127
+		return ret;
128
+
129
+	spin_lock_init(&port8250.port.lock);
130
+
131
+	port8250.port.mapbase           = regs->start;
132
+	port8250.port.irq               = irq;
133
+	port8250.port.handle_irq        = fsl8250_handle_irq;
134
+	port8250.port.type              = PORT_16550A;
135
+	port8250.port.flags             = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF
136
+						| UPF_FIXED_PORT | UPF_IOREMAP
137
+						| UPF_FIXED_TYPE;
138
+	port8250.port.dev               = dev;
139
+	port8250.port.mapsize           = resource_size(regs);
140
+	port8250.port.iotype            = UPIO_MEM;
141
+	port8250.port.irqflags          = IRQF_SHARED;
142
+
143
+	port8250.port.membase = devm_ioremap(dev,  port8250.port.mapbase,
144
+							port8250.port.mapsize);
145
+	if (!port8250.port.membase)
146
+		return -ENOMEM;
147
+
148
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
149
+	if (!data)
150
+		return -ENOMEM;
151
+
152
+	data->line = serial8250_register_8250_port(&port8250);
153
+	if (data->line < 0)
154
+		return data->line;
155
+
156
+	platform_set_drvdata(pdev, data);
157
+	return 0;
158
+}
159
+
160
+static int fsl8250_acpi_remove(struct platform_device *pdev)
161
+{
162
+	struct fsl8250_data *data = platform_get_drvdata(pdev);
163
+
164
+	serial8250_unregister_port(data->line);
165
+	return 0;
166
+}
167
+
168
+static const struct acpi_device_id fsl_8250_acpi_id[] = {
169
+	{ "NXP0018", 0 },
170
+	{ },
171
+};
172
+MODULE_DEVICE_TABLE(acpi, fsl_8250_acpi_id);
173
+
174
+static struct platform_driver fsl8250_platform_driver = {
175
+	.driver = {
176
+		.name			= "fsl-16550-uart",
177
+		.acpi_match_table	= ACPI_PTR(fsl_8250_acpi_id),
178
+	},
179
+	.probe			= fsl8250_acpi_probe,
180
+	.remove			= fsl8250_acpi_remove,
181
+};
182
+
183
+module_platform_driver(fsl8250_platform_driver);
184
+#endif