Eric Lee / smarc-fsl-linux-kernel

Download as
Browse Code ยป

Commit 5b0380c94a2e888b7858fbec6fc3ac623bc9b05a

Authored by Nat Gurumoorthy
Committed by Jean Delvare
1 parent 357b9dc6c2
Exists in master and in 39 other branches 8mp-imx_5.4.70_2.3.0, 8qm-imx_5.4.70_2.3.0, emb_imx_lf-5.15.y, emb_lf-6.1.y, imx_3.0.35_4.1.0, imx_3.10.17_1.0.1_ga, imx_3.10.53_1.1.0_ga, imx_3.14.28_1.0.0_ga, imx_4.1.15_1.0.0_ga, pitx_8mp_lf-5.10.y, rt-smarc-imx_4.1.15_1.0.0_ga, rt_linux_5.15.71, smarc-8m-android-11.0.0_2.0.0, smarc-imx6_4.14.98_2.0.0_ga, smarc-imx6_4.9.88_2.0.0_ga, smarc-imx7_4.14.98_2.0.0_ga, smarc-imx7_4.9.11_1.0.0_ga, smarc-imx7_4.9.88_2.0.0_ga, smarc-imx_3.10.53_1.1.0_ga, smarc-imx_3.14.28_1.0.0_ga, smarc-imx_4.1.15_1.0.0_ga, smarc-imx_4.9.11_1.0.0_ga, smarc-imx_4.9.51_imx8m_ga, smarc-imx_4.9.88_2.0.0_ga, smarc-m6.0.1_2.1.0-ga, smarc-n7.1.2_2.0.0-ga, smarc-rel_imx_4.1.15_1.2.0_ga, smarc_8m_00d0_imx_4.14.98_2.0.0_ga, smarc_8m_imx_4.14.78_1.0.0_ga, smarc_8m_imx_4.14.98_2.0.0_ga, smarc_8m_imx_4.19.35_1.1.0, smarc_8mm_imx_4.14.78_1.0.0_ga, smarc_8mm_imx_4.14.98_2.0.0_ga, smarc_8mm_imx_4.19.35_1.1.0, smarc_8mm_imx_5.4.24_2.1.0, smarc_8mp_lf-5.10.y, smarc_8mq_imx_5.4.24_2.1.0, smarc_8mq_lf-5.10.y, smarc_imx_lf-5.15.y

hwmon: (it87) Use request_muxed_region 

Serialize access to the hardware by using "request_muxed_region" macro
defined by Alan Cox. Call to this macro will hold off the requestor if
the resource is currently busy. "superio_enter" will return an error
if call to "request_muxed_region" fails. Rest of the code change is to
ripple an error return from superio_enter to the top level.

Signed-off-by: Nat Gurumoorthy <natg@google.com>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

Showing 1 changed file with 19 additions and 12 deletions Side-by-side Diff

drivers/hwmon/it87.c
Diff comments   View file @ 5b0380c
... ... @@ -77,15 +77,13 @@
77 77 #define DEVID 0x20 /* Register: Device ID */
78 78 #define DEVREV 0x22 /* Register: Device Revision */
79 79  
80   -static inline int
81   -superio_inb(int reg)
  80 +static inline int superio_inb(int reg)
82 81 {
83 82 outb(reg, REG);
84 83 return inb(VAL);
85 84 }
86 85  
87   -static inline void
88   -superio_outb(int reg, int val)
  86 +static inline void superio_outb(int reg, int val)
89 87 {
90 88 outb(reg, REG);
91 89 outb(val, VAL);
92 90  
93 91  
94 92  
95 93  
96 94  
... ... @@ -101,27 +99,32 @@
101 99 return val;
102 100 }
103 101  
104   -static inline void
105   -superio_select(int ldn)
  102 +static inline void superio_select(int ldn)
106 103 {
107 104 outb(DEV, REG);
108 105 outb(ldn, VAL);
109 106 }
110 107  
111   -static inline void
112   -superio_enter(void)
  108 +static inline int superio_enter(void)
113 109 {
  110 + /*
  111 + * Try to reserve REG and REG + 1 for exclusive access.
  112 + */
  113 + if (!request_muxed_region(REG, 2, DRVNAME))
  114 + return -EBUSY;
  115 +
114 116 outb(0x87, REG);
115 117 outb(0x01, REG);
116 118 outb(0x55, REG);
117 119 outb(0x55, REG);
  120 + return 0;
118 121 }
119 122  
120   -static inline void
121   -superio_exit(void)
  123 +static inline void superio_exit(void)
122 124 {
123 125 outb(0x02, REG);
124 126 outb(0x02, VAL);
  127 + release_region(REG, 2);
125 128 }
126 129  
127 130 /* Logical device 4 registers */
128 131  
... ... @@ -1542,11 +1545,15 @@
1542 1545 static int __init it87_find(unsigned short *address,
1543 1546 struct it87_sio_data *sio_data)
1544 1547 {
1545   - int err = -ENODEV;
  1548 + int err;
1546 1549 u16 chip_type;
1547 1550 const char *board_vendor, *board_name;
1548 1551  
1549   - superio_enter();
  1552 + err = superio_enter();
  1553 + if (err)
  1554 + return err;
  1555 +
  1556 + err = -ENODEV;
1550 1557 chip_type = force_id ? force_id : superio_inw(DEVID);
1551 1558  
1552 1559 switch (chip_type) {