[PATCH] Add 93cx6 eeprom library

This patch adds a library for reading from 93cx6 eeproms. Signed-off-by: Michael Wu <flamingice@sourmilk.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>

[PATCH] Add 93cx6 eeprom library
This patch adds a library for reading from 93cx6 eeproms. Signed-off-by: Michael Wu <flamingice@sourmilk.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Ivo van Doorn · Jeff Garzik
1 parent 7dcca30a32
Showing 4 changed files with 307 additions and 1 deletions Side-by-side Diff
drivers/misc/Kconfig
drivers/misc/Makefile
drivers/misc/eeprom_93cx6.c
include/linux/eeprom_93cx6.h
@@ -34,6 +34,11 @@
 	  If you choose to build module, its name will be phantom. If unsure,
 	  say N here.
  
+config EEPROM_93CX6
+	tristate "EEPROM 93CX6 support"
+	---help---
+	  This is a driver for the EEPROM chipsets 93c46 and 93c66.
+	  The driver supports both read as well as write commands.
  
 	  If unsure, say N.
  
@@ -186,7 +191,6 @@
 	  notifications when the bay lever is ejected or inserted.
  
 	  If you are not sure, say Y here.
-
  
 endmenu
@@ -14,4 +14,5 @@
 obj-$(CONFIG_SGI_IOC4)		+= ioc4.o
 obj-$(CONFIG_SONY_LAPTOP)	+= sony-laptop.o
 obj-$(CONFIG_THINKPAD_ACPI)	+= thinkpad_acpi.o
+obj-$(CONFIG_EEPROM_93CX6)	+= eeprom_93cx6.o
+/*
+	Copyright (C) 2004 - 2006 rt2x00 SourceForge Project
+	<http://rt2x00.serialmonkey.com>
+
+	This program is free software; you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation; either version 2 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to the
+	Free Software Foundation, Inc.,
+	59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+/*
+	Module: eeprom_93cx6
+	Abstract: EEPROM reader routines for 93cx6 chipsets.
+	Supported chipsets: 93c46 & 93c66.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/delay.h>
+#include <linux/eeprom_93cx6.h>
+
+MODULE_AUTHOR("http://rt2x00.serialmonkey.com");
+MODULE_VERSION("1.0");
+MODULE_DESCRIPTION("EEPROM 93cx6 chip driver");
+MODULE_LICENSE("GPL");
+
+static inline void eeprom_93cx6_pulse_high(struct eeprom_93cx6 *eeprom)
+{
+	eeprom->reg_data_clock = 1;
+	eeprom->register_write(eeprom);
+	udelay(1);
+}
+
+static inline void eeprom_93cx6_pulse_low(struct eeprom_93cx6 *eeprom)
+{
+	eeprom->reg_data_clock = 0;
+	eeprom->register_write(eeprom);
+	udelay(1);
+}
+
+static void eeprom_93cx6_startup(struct eeprom_93cx6 *eeprom)
+{
+	/*
+	 * Clear all flags, and enable chip select.
+	 */
+	eeprom->register_read(eeprom);
+	eeprom->reg_data_in = 0;
+	eeprom->reg_data_out = 0;
+	eeprom->reg_data_clock = 0;
+	eeprom->reg_chip_select = 1;
+	eeprom->register_write(eeprom);
+
+	/*
+	 * kick a pulse.
+	 */
+	eeprom_93cx6_pulse_high(eeprom);
+	eeprom_93cx6_pulse_low(eeprom);
+}
+
+static void eeprom_93cx6_cleanup(struct eeprom_93cx6 *eeprom)
+{
+	/*
+	 * Clear chip_select and data_in flags.
+	 */
+	eeprom->register_read(eeprom);
+	eeprom->reg_data_in = 0;
+	eeprom->reg_chip_select = 0;
+	eeprom->register_write(eeprom);
+
+	/*
+	 * kick a pulse.
+	 */
+	eeprom_93cx6_pulse_high(eeprom);
+	eeprom_93cx6_pulse_low(eeprom);
+}
+
+static void eeprom_93cx6_write_bits(struct eeprom_93cx6 *eeprom,
+	const u16 data, const u16 count)
+{
+	unsigned int i;
+
+	eeprom->register_read(eeprom);
+
+	/*
+	 * Clear data flags.
+	 */
+	eeprom->reg_data_in = 0;
+	eeprom->reg_data_out = 0;
+
+	/*
+	 * Start writing all bits.
+	 */
+	for (i = count; i > 0; i--) {
+		/*
+		 * Check if this bit needs to be set.
+		 */
+		eeprom->reg_data_in = !!(data & (1 << (i - 1)));
+
+		/*
+		 * Write the bit to the eeprom register.
+		 */
+		eeprom->register_write(eeprom);
+
+		/*
+		 * Kick a pulse.
+		 */
+		eeprom_93cx6_pulse_high(eeprom);
+		eeprom_93cx6_pulse_low(eeprom);
+	}
+
+	eeprom->reg_data_in = 0;
+	eeprom->register_write(eeprom);
+}
+
+static void eeprom_93cx6_read_bits(struct eeprom_93cx6 *eeprom,
+	u16 *data, const u16 count)
+{
+	unsigned int i;
+	u16 buf = 0;
+
+	eeprom->register_read(eeprom);
+
+	/*
+	 * Clear data flags.
+	 */
+	eeprom->reg_data_in = 0;
+	eeprom->reg_data_out = 0;
+
+	/*
+	 * Start reading all bits.
+	 */
+	for (i = count; i > 0; i--) {
+		eeprom_93cx6_pulse_high(eeprom);
+
+		eeprom->register_read(eeprom);
+
+		/*
+		 * Clear data_in flag.
+		 */
+		eeprom->reg_data_in = 0;
+
+		/*
+		 * Read if the bit has been set.
+		 */
+		if (eeprom->reg_data_out)
+			buf |= (1 << (i - 1));
+
+		eeprom_93cx6_pulse_low(eeprom);
+	}
+
+	*data = buf;
+}
+
+/**
+ * eeprom_93cx6_read - Read multiple words from eeprom
+ * @eeprom: Pointer to eeprom structure
+ * @word: Word index from where we should start reading
+ * @data: target pointer where the information will have to be stored
+ *
+ * This function will read the eeprom data as host-endian word
+ * into the given data pointer.
+ */
+void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word,
+	u16 *data)
+{
+	u16 command;
+
+	/*
+	 * Initialize the eeprom register
+	 */
+	eeprom_93cx6_startup(eeprom);
+
+	/*
+	 * Select the read opcode and the word to be read.
+	 */
+	command = (PCI_EEPROM_READ_OPCODE << eeprom->width) | word;
+	eeprom_93cx6_write_bits(eeprom, command,
+		PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
+
+	/*
+	 * Read the requested 16 bits.
+	 */
+	eeprom_93cx6_read_bits(eeprom, data, 16);
+
+	/*
+	 * Cleanup eeprom register.
+	 */
+	eeprom_93cx6_cleanup(eeprom);
+}
+EXPORT_SYMBOL_GPL(eeprom_93cx6_read);
+
+/**
+ * eeprom_93cx6_multiread - Read multiple words from eeprom
+ * @eeprom: Pointer to eeprom structure
+ * @word: Word index from where we should start reading
+ * @data: target pointer where the information will have to be stored
+ * @words: Number of words that should be read.
+ *
+ * This function will read all requested words from the eeprom,
+ * this is done by calling eeprom_93cx6_read() multiple times.
+ * But with the additional change that while the eeprom_93cx6_read
+ * will return host ordered bytes, this method will return little
+ * endian words.
+ */
+void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, const u8 word,
+	__le16 *data, const u16 words)
+{
+	unsigned int i;
+	u16 tmp;
+
+	for (i = 0; i < words; i++) {
+		tmp = 0;
+		eeprom_93cx6_read(eeprom, word + i, &tmp);
+		data[i] = cpu_to_le16(tmp);
+	}
+}
+EXPORT_SYMBOL_GPL(eeprom_93cx6_multiread);
+/*
+	Copyright (C) 2004 - 2006 rt2x00 SourceForge Project
+	<http://rt2x00.serialmonkey.com>
+
+	This program is free software; you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation; either version 2 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to the
+	Free Software Foundation, Inc.,
+	59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+/*
+	Module: eeprom_93cx6
+	Abstract: EEPROM reader datastructures for 93cx6 chipsets.
+	Supported chipsets: 93c46 & 93c66.
+ */
+
+/*
+ * EEPROM operation defines.
+ */
+#define PCI_EEPROM_WIDTH_93C46	6
+#define PCI_EEPROM_WIDTH_93C66	8
+#define PCI_EEPROM_WIDTH_OPCODE	3
+#define PCI_EEPROM_WRITE_OPCODE	0x05
+#define PCI_EEPROM_READ_OPCODE	0x06
+#define PCI_EEPROM_EWDS_OPCODE	0x10
+#define PCI_EEPROM_EWEN_OPCODE	0x13
+
+/**
+ * struct eeprom_93cx6 - control structure for setting the commands
+ * for reading the eeprom data.
+ * @data: private pointer for the driver.
+ * @register_read(struct eeprom_93cx6 *eeprom): handler to
+ * read the eeprom register, this function should set all reg_* fields.
+ * @register_write(struct eeprom_93cx6 *eeprom): handler to
+ * write to the eeprom register by using all reg_* fields.
+ * @width: eeprom width, should be one of the PCI_EEPROM_WIDTH_* defines
+ * @reg_data_in: register field to indicate data input
+ * @reg_data_out: register field to indicate data output
+ * @reg_data_clock: register field to set the data clock
+ * @reg_chip_select: register field to set the chip select
+ *
+ * This structure is used for the communication between the driver
+ * and the eeprom_93cx6 handlers for reading the eeprom.
+ */
+struct eeprom_93cx6 {
+	void *data;
+
+	void (*register_read)(struct eeprom_93cx6 *eeprom);
+	void (*register_write)(struct eeprom_93cx6 *eeprom);
+
+	int width;
+
+	char reg_data_in;
+	char reg_data_out;
+	char reg_data_clock;
+	char reg_chip_select;
+};
+
+extern void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom,
+	const u8 word, u16 *data);
+extern void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom,
+	const u8 word, __le16 *data, const u16 words);
...	...	@@ -34,6 +34,11 @@
34	34	If you choose to build module, its name will be phantom. If unsure,
35	35	say N here.
36	36
	37	+config EEPROM_93CX6
	38	+ tristate "EEPROM 93CX6 support"
	39	+ ---help---
	40	+ This is a driver for the EEPROM chipsets 93c46 and 93c66.
	41	+ The driver supports both read as well as write commands.
37	42
38	43	If unsure, say N.
39	44
...	...	@@ -186,7 +191,6 @@
186	191	notifications when the bay lever is ejected or inserted.
187	192
188	193	If you are not sure, say Y here.
189		-
190	194
191	195	endmenu
...	...	@@ -14,4 +14,5 @@
14	14	obj-$(CONFIG_SGI_IOC4) += ioc4.o
15	15	obj-$(CONFIG_SONY_LAPTOP) += sony-laptop.o
16	16	obj-$(CONFIG_THINKPAD_ACPI) += thinkpad_acpi.o
	17	+obj-$(CONFIG_EEPROM_93CX6) += eeprom_93cx6.o
	1	+/*
	2	+ Copyright (C) 2004 - 2006 rt2x00 SourceForge Project
	3	+ <http://rt2x00.serialmonkey.com>
	4	+
	5	+ This program is free software; you can redistribute it and/or modify
	6	+ it under the terms of the GNU General Public License as published by
	7	+ the Free Software Foundation; either version 2 of the License, or
	8	+ (at your option) any later version.
	9	+
	10	+ This program is distributed in the hope that it will be useful,
	11	+ but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	+ GNU General Public License for more details.
	14	+
	15	+ You should have received a copy of the GNU General Public License
	16	+ along with this program; if not, write to the
	17	+ Free Software Foundation, Inc.,
	18	+ 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	19	+ */
	20	+
	21	+/*
	22	+ Module: eeprom_93cx6
	23	+ Abstract: EEPROM reader routines for 93cx6 chipsets.
	24	+ Supported chipsets: 93c46 & 93c66.
	25	+ */
	26	+
	27	+#include <linux/kernel.h>
	28	+#include <linux/module.h>
	29	+#include <linux/version.h>
	30	+#include <linux/delay.h>
	31	+#include <linux/eeprom_93cx6.h>
	32	+
	33	+MODULE_AUTHOR("http://rt2x00.serialmonkey.com");
	34	+MODULE_VERSION("1.0");
	35	+MODULE_DESCRIPTION("EEPROM 93cx6 chip driver");
	36	+MODULE_LICENSE("GPL");
	37	+
	38	+static inline void eeprom_93cx6_pulse_high(struct eeprom_93cx6 *eeprom)
	39	+{
	40	+ eeprom->reg_data_clock = 1;
	41	+ eeprom->register_write(eeprom);
	42	+ udelay(1);
	43	+}
	44	+
	45	+static inline void eeprom_93cx6_pulse_low(struct eeprom_93cx6 *eeprom)
	46	+{
	47	+ eeprom->reg_data_clock = 0;
	48	+ eeprom->register_write(eeprom);
	49	+ udelay(1);
	50	+}
	51	+
	52	+static void eeprom_93cx6_startup(struct eeprom_93cx6 *eeprom)
	53	+{
	54	+ /*
	55	+ * Clear all flags, and enable chip select.
	56	+ */
	57	+ eeprom->register_read(eeprom);
	58	+ eeprom->reg_data_in = 0;
	59	+ eeprom->reg_data_out = 0;
	60	+ eeprom->reg_data_clock = 0;
	61	+ eeprom->reg_chip_select = 1;
	62	+ eeprom->register_write(eeprom);
	63	+
	64	+ /*
	65	+ * kick a pulse.
	66	+ */
	67	+ eeprom_93cx6_pulse_high(eeprom);
	68	+ eeprom_93cx6_pulse_low(eeprom);
	69	+}
	70	+
	71	+static void eeprom_93cx6_cleanup(struct eeprom_93cx6 *eeprom)
	72	+{
	73	+ /*
	74	+ * Clear chip_select and data_in flags.
	75	+ */
	76	+ eeprom->register_read(eeprom);
	77	+ eeprom->reg_data_in = 0;
	78	+ eeprom->reg_chip_select = 0;
	79	+ eeprom->register_write(eeprom);
	80	+
	81	+ /*
	82	+ * kick a pulse.
	83	+ */
	84	+ eeprom_93cx6_pulse_high(eeprom);
	85	+ eeprom_93cx6_pulse_low(eeprom);
	86	+}
	87	+
	88	+static void eeprom_93cx6_write_bits(struct eeprom_93cx6 *eeprom,
	89	+ const u16 data, const u16 count)
	90	+{
	91	+ unsigned int i;
	92	+
	93	+ eeprom->register_read(eeprom);
	94	+
	95	+ /*
	96	+ * Clear data flags.
	97	+ */
	98	+ eeprom->reg_data_in = 0;
	99	+ eeprom->reg_data_out = 0;
	100	+
	101	+ /*
	102	+ * Start writing all bits.
	103	+ */
	104	+ for (i = count; i > 0; i--) {
	105	+ /*
	106	+ * Check if this bit needs to be set.
	107	+ */
	108	+ eeprom->reg_data_in = !!(data & (1 << (i - 1)));
	109	+
	110	+ /*
	111	+ * Write the bit to the eeprom register.
	112	+ */
	113	+ eeprom->register_write(eeprom);
	114	+
	115	+ /*
	116	+ * Kick a pulse.
	117	+ */
	118	+ eeprom_93cx6_pulse_high(eeprom);
	119	+ eeprom_93cx6_pulse_low(eeprom);
	120	+ }
	121	+
	122	+ eeprom->reg_data_in = 0;
	123	+ eeprom->register_write(eeprom);
	124	+}
	125	+
	126	+static void eeprom_93cx6_read_bits(struct eeprom_93cx6 *eeprom,
	127	+ u16 *data, const u16 count)
	128	+{
	129	+ unsigned int i;
	130	+ u16 buf = 0;
	131	+
	132	+ eeprom->register_read(eeprom);
	133	+
	134	+ /*
	135	+ * Clear data flags.
	136	+ */
	137	+ eeprom->reg_data_in = 0;
	138	+ eeprom->reg_data_out = 0;
	139	+
	140	+ /*
	141	+ * Start reading all bits.
	142	+ */
	143	+ for (i = count; i > 0; i--) {
	144	+ eeprom_93cx6_pulse_high(eeprom);
	145	+
	146	+ eeprom->register_read(eeprom);
	147	+
	148	+ /*
	149	+ * Clear data_in flag.
	150	+ */
	151	+ eeprom->reg_data_in = 0;
	152	+
	153	+ /*
	154	+ * Read if the bit has been set.
	155	+ */
	156	+ if (eeprom->reg_data_out)
	157	+ buf \|= (1 << (i - 1));
	158	+
	159	+ eeprom_93cx6_pulse_low(eeprom);
	160	+ }
	161	+
	162	+ *data = buf;
	163	+}
	164	+
	165	+/**
	166	+ * eeprom_93cx6_read - Read multiple words from eeprom
	167	+ * @eeprom: Pointer to eeprom structure
	168	+ * @word: Word index from where we should start reading
	169	+ * @data: target pointer where the information will have to be stored
	170	+ *
	171	+ * This function will read the eeprom data as host-endian word
	172	+ * into the given data pointer.
	173	+ */
	174	+void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word,
	175	+ u16 *data)
	176	+{
	177	+ u16 command;
	178	+
	179	+ /*
	180	+ * Initialize the eeprom register
	181	+ */
	182	+ eeprom_93cx6_startup(eeprom);
	183	+
	184	+ /*
	185	+ * Select the read opcode and the word to be read.
	186	+ */
	187	+ command = (PCI_EEPROM_READ_OPCODE << eeprom->width) \| word;
	188	+ eeprom_93cx6_write_bits(eeprom, command,
	189	+ PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
	190	+
	191	+ /*
	192	+ * Read the requested 16 bits.
	193	+ */
	194	+ eeprom_93cx6_read_bits(eeprom, data, 16);
	195	+
	196	+ /*
	197	+ * Cleanup eeprom register.
	198	+ */
	199	+ eeprom_93cx6_cleanup(eeprom);
	200	+}
	201	+EXPORT_SYMBOL_GPL(eeprom_93cx6_read);
	202	+
	203	+/**
	204	+ * eeprom_93cx6_multiread - Read multiple words from eeprom
	205	+ * @eeprom: Pointer to eeprom structure
	206	+ * @word: Word index from where we should start reading
	207	+ * @data: target pointer where the information will have to be stored
	208	+ * @words: Number of words that should be read.
	209	+ *
	210	+ * This function will read all requested words from the eeprom,
	211	+ * this is done by calling eeprom_93cx6_read() multiple times.
	212	+ * But with the additional change that while the eeprom_93cx6_read
	213	+ * will return host ordered bytes, this method will return little
	214	+ * endian words.
	215	+ */
	216	+void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, const u8 word,
	217	+ __le16 *data, const u16 words)
	218	+{
	219	+ unsigned int i;
	220	+ u16 tmp;
	221	+
	222	+ for (i = 0; i < words; i++) {
	223	+ tmp = 0;
	224	+ eeprom_93cx6_read(eeprom, word + i, &tmp);
	225	+ data[i] = cpu_to_le16(tmp);
	226	+ }
	227	+}
	228	+EXPORT_SYMBOL_GPL(eeprom_93cx6_multiread);