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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/auxdisplay/hd44780_common.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/auxdisplay/hd44780_common.c')
-rw-r--r--drivers/auxdisplay/hd44780_common.c361
1 files changed, 361 insertions, 0 deletions
diff --git a/drivers/auxdisplay/hd44780_common.c b/drivers/auxdisplay/hd44780_common.c
new file mode 100644
index 000000000..3934c2eeb
--- /dev/null
+++ b/drivers/auxdisplay/hd44780_common.c
@@ -0,0 +1,361 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include "charlcd.h"
+#include "hd44780_common.h"
+
+/* LCD commands */
+#define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */
+
+#define LCD_CMD_ENTRY_MODE 0x04 /* Set entry mode */
+#define LCD_CMD_CURSOR_INC 0x02 /* Increment cursor */
+
+#define LCD_CMD_DISPLAY_CTRL 0x08 /* Display control */
+#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
+#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
+#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */
+
+#define LCD_CMD_SHIFT 0x10 /* Shift cursor/display */
+#define LCD_CMD_DISPLAY_SHIFT 0x08 /* Shift display instead of cursor */
+#define LCD_CMD_SHIFT_RIGHT 0x04 /* Shift display/cursor to the right */
+
+#define LCD_CMD_FUNCTION_SET 0x20 /* Set function */
+#define LCD_CMD_DATA_LEN_8BITS 0x10 /* Set data length to 8 bits */
+#define LCD_CMD_TWO_LINES 0x08 /* Set to two display lines */
+#define LCD_CMD_FONT_5X10_DOTS 0x04 /* Set char font to 5x10 dots */
+
+#define LCD_CMD_SET_CGRAM_ADDR 0x40 /* Set char generator RAM address */
+
+#define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */
+
+/* sleeps that many milliseconds with a reschedule */
+static void long_sleep(int ms)
+{
+ schedule_timeout_interruptible(msecs_to_jiffies(ms));
+}
+
+int hd44780_common_print(struct charlcd *lcd, int c)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ if (lcd->addr.x < hdc->bwidth) {
+ hdc->write_data(hdc, c);
+ return 0;
+ }
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_print);
+
+int hd44780_common_gotoxy(struct charlcd *lcd, unsigned int x, unsigned int y)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+ unsigned int addr;
+
+ /*
+ * we force the cursor to stay at the end of the
+ * line if it wants to go farther
+ */
+ addr = x < hdc->bwidth ? x & (hdc->hwidth - 1) : hdc->bwidth - 1;
+ if (y & 1)
+ addr += hdc->hwidth;
+ if (y & 2)
+ addr += hdc->bwidth;
+ hdc->write_cmd(hdc, LCD_CMD_SET_DDRAM_ADDR | addr);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_gotoxy);
+
+int hd44780_common_home(struct charlcd *lcd)
+{
+ return hd44780_common_gotoxy(lcd, 0, 0);
+}
+EXPORT_SYMBOL_GPL(hd44780_common_home);
+
+/* clears the display and resets X/Y */
+int hd44780_common_clear_display(struct charlcd *lcd)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CLEAR);
+ /* datasheet says to wait 1,64 milliseconds */
+ long_sleep(2);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_clear_display);
+
+int hd44780_common_init_display(struct charlcd *lcd)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ void (*write_cmd_raw)(struct hd44780_common *hdc, int cmd);
+ u8 init;
+
+ if (hdc->ifwidth != 4 && hdc->ifwidth != 8)
+ return -EINVAL;
+
+ hdc->hd44780_common_flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) |
+ LCD_FLAG_D | LCD_FLAG_C | LCD_FLAG_B;
+
+ long_sleep(20); /* wait 20 ms after power-up for the paranoid */
+
+ /*
+ * 8-bit mode, 1 line, small fonts; let's do it 3 times, to make sure
+ * the LCD is in 8-bit mode afterwards
+ */
+ init = LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS;
+ if (hdc->ifwidth == 4) {
+ init >>= 4;
+ write_cmd_raw = hdc->write_cmd_raw4;
+ } else {
+ write_cmd_raw = hdc->write_cmd;
+ }
+ write_cmd_raw(hdc, init);
+ long_sleep(10);
+ write_cmd_raw(hdc, init);
+ long_sleep(10);
+ write_cmd_raw(hdc, init);
+ long_sleep(10);
+
+ if (hdc->ifwidth == 4) {
+ /* Switch to 4-bit mode, 1 line, small fonts */
+ hdc->write_cmd_raw4(hdc, LCD_CMD_FUNCTION_SET >> 4);
+ long_sleep(10);
+ }
+
+ /* set font height and lines number */
+ hdc->write_cmd(hdc,
+ LCD_CMD_FUNCTION_SET |
+ ((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
+ ((hdc->hd44780_common_flags & LCD_FLAG_F) ?
+ LCD_CMD_FONT_5X10_DOTS : 0) |
+ ((hdc->hd44780_common_flags & LCD_FLAG_N) ?
+ LCD_CMD_TWO_LINES : 0));
+ long_sleep(10);
+
+ /* display off, cursor off, blink off */
+ hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CTRL);
+ long_sleep(10);
+
+ hdc->write_cmd(hdc,
+ LCD_CMD_DISPLAY_CTRL | /* set display mode */
+ ((hdc->hd44780_common_flags & LCD_FLAG_D) ?
+ LCD_CMD_DISPLAY_ON : 0) |
+ ((hdc->hd44780_common_flags & LCD_FLAG_C) ?
+ LCD_CMD_CURSOR_ON : 0) |
+ ((hdc->hd44780_common_flags & LCD_FLAG_B) ?
+ LCD_CMD_BLINK_ON : 0));
+
+ charlcd_backlight(lcd,
+ (hdc->hd44780_common_flags & LCD_FLAG_L) ? 1 : 0);
+
+ long_sleep(10);
+
+ /* entry mode set : increment, cursor shifting */
+ hdc->write_cmd(hdc, LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);
+
+ hd44780_common_clear_display(lcd);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_init_display);
+
+int hd44780_common_shift_cursor(struct charlcd *lcd, enum charlcd_shift_dir dir)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ if (dir == CHARLCD_SHIFT_LEFT) {
+ /* back one char if not at end of line */
+ if (lcd->addr.x < hdc->bwidth)
+ hdc->write_cmd(hdc, LCD_CMD_SHIFT);
+ } else if (dir == CHARLCD_SHIFT_RIGHT) {
+ /* allow the cursor to pass the end of the line */
+ if (lcd->addr.x < (hdc->bwidth - 1))
+ hdc->write_cmd(hdc,
+ LCD_CMD_SHIFT | LCD_CMD_SHIFT_RIGHT);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_shift_cursor);
+
+int hd44780_common_shift_display(struct charlcd *lcd,
+ enum charlcd_shift_dir dir)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ if (dir == CHARLCD_SHIFT_LEFT)
+ hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
+ else if (dir == CHARLCD_SHIFT_RIGHT)
+ hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
+ LCD_CMD_SHIFT_RIGHT);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_shift_display);
+
+static void hd44780_common_set_mode(struct hd44780_common *hdc)
+{
+ hdc->write_cmd(hdc,
+ LCD_CMD_DISPLAY_CTRL |
+ ((hdc->hd44780_common_flags & LCD_FLAG_D) ?
+ LCD_CMD_DISPLAY_ON : 0) |
+ ((hdc->hd44780_common_flags & LCD_FLAG_C) ?
+ LCD_CMD_CURSOR_ON : 0) |
+ ((hdc->hd44780_common_flags & LCD_FLAG_B) ?
+ LCD_CMD_BLINK_ON : 0));
+}
+
+int hd44780_common_display(struct charlcd *lcd, enum charlcd_onoff on)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ if (on == CHARLCD_ON)
+ hdc->hd44780_common_flags |= LCD_FLAG_D;
+ else
+ hdc->hd44780_common_flags &= ~LCD_FLAG_D;
+
+ hd44780_common_set_mode(hdc);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_display);
+
+int hd44780_common_cursor(struct charlcd *lcd, enum charlcd_onoff on)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ if (on == CHARLCD_ON)
+ hdc->hd44780_common_flags |= LCD_FLAG_C;
+ else
+ hdc->hd44780_common_flags &= ~LCD_FLAG_C;
+
+ hd44780_common_set_mode(hdc);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_cursor);
+
+int hd44780_common_blink(struct charlcd *lcd, enum charlcd_onoff on)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ if (on == CHARLCD_ON)
+ hdc->hd44780_common_flags |= LCD_FLAG_B;
+ else
+ hdc->hd44780_common_flags &= ~LCD_FLAG_B;
+
+ hd44780_common_set_mode(hdc);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_blink);
+
+static void hd44780_common_set_function(struct hd44780_common *hdc)
+{
+ hdc->write_cmd(hdc,
+ LCD_CMD_FUNCTION_SET |
+ ((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
+ ((hdc->hd44780_common_flags & LCD_FLAG_F) ?
+ LCD_CMD_FONT_5X10_DOTS : 0) |
+ ((hdc->hd44780_common_flags & LCD_FLAG_N) ?
+ LCD_CMD_TWO_LINES : 0));
+}
+
+int hd44780_common_fontsize(struct charlcd *lcd, enum charlcd_fontsize size)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ if (size == CHARLCD_FONTSIZE_LARGE)
+ hdc->hd44780_common_flags |= LCD_FLAG_F;
+ else
+ hdc->hd44780_common_flags &= ~LCD_FLAG_F;
+
+ hd44780_common_set_function(hdc);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_fontsize);
+
+int hd44780_common_lines(struct charlcd *lcd, enum charlcd_lines lines)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ if (lines == CHARLCD_LINES_2)
+ hdc->hd44780_common_flags |= LCD_FLAG_N;
+ else
+ hdc->hd44780_common_flags &= ~LCD_FLAG_N;
+
+ hd44780_common_set_function(hdc);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_lines);
+
+int hd44780_common_redefine_char(struct charlcd *lcd, char *esc)
+{
+ /* Generator : LGcxxxxx...xx; must have <c> between '0'
+ * and '7', representing the numerical ASCII code of the
+ * redefined character, and <xx...xx> a sequence of 16
+ * hex digits representing 8 bytes for each character.
+ * Most LCDs will only use 5 lower bits of the 7 first
+ * bytes.
+ */
+
+ struct hd44780_common *hdc = lcd->drvdata;
+ unsigned char cgbytes[8];
+ unsigned char cgaddr;
+ int cgoffset;
+ int shift;
+ char value;
+ int addr;
+
+ if (!strchr(esc, ';'))
+ return 0;
+
+ esc++;
+
+ cgaddr = *(esc++) - '0';
+ if (cgaddr > 7)
+ return 1;
+
+ cgoffset = 0;
+ shift = 0;
+ value = 0;
+ while (*esc && cgoffset < 8) {
+ int half;
+
+ shift ^= 4;
+ half = hex_to_bin(*esc++);
+ if (half < 0)
+ continue;
+
+ value |= half << shift;
+ if (shift == 0) {
+ cgbytes[cgoffset++] = value;
+ value = 0;
+ }
+ }
+
+ hdc->write_cmd(hdc, LCD_CMD_SET_CGRAM_ADDR | (cgaddr * 8));
+ for (addr = 0; addr < cgoffset; addr++)
+ hdc->write_data(hdc, cgbytes[addr]);
+
+ /* ensures that we stop writing to CGRAM */
+ lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
+ return 1;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_redefine_char);
+
+struct hd44780_common *hd44780_common_alloc(void)
+{
+ struct hd44780_common *hd;
+
+ hd = kzalloc(sizeof(*hd), GFP_KERNEL);
+ if (!hd)
+ return NULL;
+
+ hd->ifwidth = 8;
+ hd->bwidth = DEFAULT_LCD_BWIDTH;
+ hd->hwidth = DEFAULT_LCD_HWIDTH;
+ return hd;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_alloc);
+
+MODULE_LICENSE("GPL");